1Introduction

Information and Computer Technology (ICT) is weaving into the fabric of our city and becomes a pervasive medium, which accompanies our daily life. New mediums such as public displays and media façades expand the range of technology already part of the city. They also become more interactive and researchers investigate alternative uses of these technologies, which lie beyond efficiency. Human-Computer Interaction (HCI) researchers turned their interest from information displays towards more playful applications, which foster social interaction or strengthen identification with the city. Often interface designs for public displays or media architecture focused on directly accessing information provided by them, but forgot about what happens in front of the screen while the information is consumed. Does it enliven the situation? Is it preventing social interaction? In this book information is considered as constructional material on a par with traditional building materials. This emphasizes the responsibility in what way technology should be applied in our cities. Providing information access through a specific system design changes public behavior. This is similar to designing a public square. Designed in a right way it can provide the basis for a vibrant place, but done wrong it can also turn a space into a deserted area.

However, little is known about how these situated interfaces shape public space. Defining and making space is the task of urban designers and architects, but as HCI invents novel types of interfaces for the urban environment, spatial thinking as well as understanding the different types of values for public spaces becomes necessary for this research domain.

1.1Motivation

The motivation of writing this chapter is driven by the obvious fallacy that Human-Computer Interaction scientists are able to create new media systems for public spaces without making the same mistakes urban planners and architects have done in the past. Currently, we live in an age where more and more sensors are soaking into our cities with the predominant purpose to monitor our environment and to capitalize upon it. Mobility control, smart water networks, parking space management, surveillance systems, and air pollution monitoring are only a few typical application domains for Information and Communication Technology (ICT) within our city. In contrast to sensing the city, actuating the city is left to digital advertisers and real estate developers. According to Hilmar von Lojewski, a Deputy of the German Städtetag, corporations currently prepare for the digital land grab by means of standardization under the flag of the “Smart City” (Lojewski 2014). In this regard only few institutions feel responsible to support cultural aspects through our new digital means. Among these are media artists who criticise the digital development of our cities (e.g. Julian Oliver with his artwork ‘The Artvertiser’ (Oliver 2008–2010)), hacktivists who disrupt in order to address serious deficits in the field of urban planning (e.g. TV-B-Gone by Mitch Altman (Altman 2009), Skullphone (SKULLPHONE)), parkour and skateboard practitioners who take an alternative and creative approach on architecture and culture (cf. (Borden 2001)), and freifunkers who create free wireless community networks. Surprisingly, these grassroots movements seem to contribute more positively to a digital city than city councils themselves due to the fact they maintain space, without monetary capitalisation in mind. They provide alternative views, value creativity and instead build cultural capital. Unfortunately, it seems that current master plans rarely include methods on how to increase these cultural values through todays evolving and already highly advanced digital means.

However, this chapter will not provide a tailored recommended plan of action for a good digital urban design, but is certainly motivated by the antiquated view of city councils on media technology. Various ICT paradigms are changing our city as shown in Figure 1.

Our research interest leans towards the idea of the Humane City and Urban HCI. Urban HCI builds on former visions of ICT merging with the city, but it also differentiates itself from it. How so, will be described in the following.

Digital displays are becoming more and more ubiquitous: they range from smaller displays, providing information such as bus schedules, to bigger ones showing latest discounts in shopping malls and retail stores, to large-scale displays covering an entire building façade (Kostakos/Ojala 2013). Although most displays act as digital signage, supporting no interaction, recent advances in technology are rapidly changing this and turn them into interactive and user-engaging technology, ultimately leading to an open and novel communications medium (Davies et al. 2012). However, most focus on spreading or gathering information efficiently and often do so by connecting to internet emergent communication technology schemes, such as social networks (Schroeter 2012) and email. System developers, however, too often forget about their situatedness, and frequently transfer global communication systems onto the streets. For example, mobile texting to a public display is a common application. By seeking out alternatives in media art and grassroots movements, innovative HCI systems can be found which enrich our everyday life (e.g. Solar Pink Pong (Assocreation 2014)). Generally, the problem is to reason what values should be preferably promoted through digital systems. City system solution developers for e.g. parking systems or out-of-home advertising can provide a monetary benefit to the city and seem to sell easier than those that develop cultural capital.

However, since 2008 the Media Façade Festival was able to gain traction in providing alternative media formats for European cities. Extending the initiative to a European festival in 2010 including seven cities, the initiative has grown to a European Urban Media Network covering the topics of the Networked City (2013), the Participatory City (2014) and the In/Visible City (2015). With being a contributing artist in 2008 and 2010, it became obvious, that great interactive projects were developed without systematic reflection. This is changing currently with the collaboration between the Media Architecture Biennale (MAB) an ACM supported conference since 2012 and the Media Façade Festival initiative, as well as the so-called “urban”-tracks in established conferences such as CHI and DIS.

2From Ubiquitous and Urban Computing to Urban HCI

Beforewe begin to answer the question of which values Media Architecture should promote in the urban environment, we explain why Media Architecture requires a different thinking than the paradigms of Ubiquitous and Urban Computing and why a new paradigm is needed. For this we will focus on conceived space, a concept of Lefebvre’s three-fold division of space (conceived space, lived space and perceived space) (Lefebvre 1991, p. 38f). Conceived spaces express a certain understanding of a place that its designers’ had in mind when constructing it (Silva/Hjorth 2009). These designers typically were architects, urban planners, urban designers, etc. and nowadays with academic disciplines such as Media Architecture, architecture orients towards the digital. In the opposing direction, HCI researchers from the fields of tangible computing (which has its origins in ubiquitous computing), physical computing, computer supported cooperative work (CSCW), and mobile computing head into public space; now also constructing novel spaces, shaping experiences and behaviours. By doing so, similar problems as architects encountered on an everyday basis are also on the technologists’ agenda, for example what values should be promoted in public space. A new set of design concerns arose, including managing attention, incorporating context, combining devices, the need for new physical forms and affordances and new interactive styles; all of these are aspects Ubiquitous Computing is interested in. However, these seem to miss architectural aspects that create our public space and shapes, to an extent, our public life.

We briefly attempt to argue in a similar way architectural theory might, to emphasize the role of space when designing digital systems installed in the public sphere.

The roman architect and architectural theorist Vitruvius based the definition of architecture on the three principles of stability, utility and grace. While the first two topics are also reasonable in software architecture, grace is an aesthetic concept. Stability and utility are a strongly connected to Ubicomp and Urban Computing. To quote a definition of Urban Computing of Microsoft Research:

Urban computing is a process of acquisition, integration, and analysis of big and heterogeneous data generated by a diversity of sources in urban spaces, such as sensors, devices, vehicles, buildings, and human, to tackle the major issues that cities face, e.g. air pollution, increased energy consumption and traffic congestion. Urban computing connects unobtrusive and ubiquitous sensing technologies, advanced data management and analytics models, and novel visualization methods, to create win-win-win solutions that improve urban environment, human life quality, and city operation systems. Urban computing also helps us understand the nature of urban phenomena and even predict the future of cities.

(Zheng et al. 2014)

In essence it rather concerned with fusing computing science with traditional fields such as transportation, civil engineering and economy in the context of urban spaces. Key challenges named by Zheng are urban sensing and data acquisition, computing with heterogeneous data and hybrid systems that blend the physical and virtual worlds (Zheng et al. 2014) (compare also to Figure 1). From that it seems Urban Computing is less concerned with the principle of grace (in the original Latin: venustas also translated as beauty and delight).

With the term venustas Vitruvius considers not only the objects of architecture as important, but already their ‘audience’. This translates in architecture often to qualities of building design, scale, proportionality of visual interesting experiences, vistas, places with unique and special character, and memorable places.

For HCI, venustas is certainly more a concern in interaction design, interface design, user experience design and industrial design. This means Urban HCI also leans more to these disciplines rather than these of ergonomics, usability engineering, cognitive science or psychology (all disciplines of HCI). The closest discipline to architecture in this respect is Ubiquitous Computing as we can recognize from conferences research papers. However, one reason we see for developing the idea of Urban HCI is, that Yong Liu et al. found through an analysis of 15 years long publication period of HUC (Handheld and Ubiquitous Computing), UbiComp and Pervasive conferences, that Ubiquitous Computing is increasingly focusing on mobile devices (Liu et al. 2014). They also predict that sensing-related studies will become increasingly core topics given the increase of sensors available in mobile devices nowadays. This actually means that Ubiquitous Computing moves in the opposite direction. Instead of integrating (digital) beauty (venustas as defined above) into architecture/city, it rather abstracts space even further.

In the following, we first compare the differences in spatial thinking between architects and computer scientists. This also serves to narrow down on what scale Urban HCI should focus on to generate an integrated sense of grace as it is understood in architecture. Subsequently we will focus on additional values extracted from various disciplines, which Urban HCI should adopt to enliven and stimulate public space gracefully.

3Scale in Architecture, Ubiquitous Computing and Urban HCI

In architecture spatial relations between the body and the built environment have been discussed at depth for thousands of years. With dimensioning being considered one of the most important tasks in architecture, it is deeply rooted in the proportions of man. The examples of the Vitruvian Man by Leonardo da Vinci (1490) based on Vitruvius writings (De architectura, 15 BC), the Modulor, devised by Le Corbusier (1934), and the human body after Ernst Neufert (1936) illustrate the relevancy. With knowledge about the Fibonacci sequence (known since ancient times ~300 BC) and an interest in proportions, Adolf Zeising (Zeising 1854) uncovered the universal law that links nature, body and art. In 1854 he for the first time described the Golden Ratio within the proportions of the human body, thus providing an objective measure and usable rule to analyse and intentionally create aesthetic relations in objects, paintings, architecture, based on nature. Both Le Corbusier and Neufert popularized this ratio in architecture by using it as a foundation found in all nature and the human body. For example, for Neufert qualitativemeasures, such as harmony in architecture can be linked to the Golden Ratio within the natural body, which eventually constitutes an objective measure.

While in architecture as a discipline aesthetic reasoning through spatial relations was always present, computer science developed spatial concepts independent of aesthetic and without a bodily ground. Mark Weiser’s ubiquity of the computers, which “weave themselves into the fabric of everyday life until they are indistinguishable from it” (Weiser 1999), is often envisioned or interpreted as a homogeneous digital layer on our cities rather than emphasizing different densities of digitality, which exists in relation to each other.

Affecting everything rather than selected environments seemed to drive application developments in Ubiquitous Computing. With mobile phone technology becoming popular in the late 90ies, applications for the city were almost predefined in terms of spatial use. For example, large urban games were developed in HCI from ~2000 on, trying to weave technology more into the city, but actually transferring attention into the virtual realm. While researchers like Adriana de Souza e Silva aim to contextualize these urban mobile phone applications to architecture, there still seems to exist a lack of understanding of how to create harmony between technology (ICT), the body and architecture. In (Silva/Hjorth 2009) de Souza e Silva points out that modes like the haptic and aural (modes often used for urban games using mobiles) override the visual that was so important for Charles Baudelaire’s flâneur. By introducing technology into the human-architecture relation, we often seem to interrupt this bond unknowingly. Consuming the city like a flâneur does seems to become secondary. This is exemplified by de Souza e Silva in an historic account (Silva/Hjorth 2009) about urban games like B.U.G (2003), Shoot me if you can (2005), Conquest (2004), Noderunner (2003), Urban Tapestries (2002–2004) (Lane et al. 2005), INP urban vibe, etc. where the city is only used as a game board. However, from her account it is also visible that relations between technology and architecture grew stronger throughout the years using location based technologies or augmented reality to create location-based mobile games (LBMG) like ‘Botfight’, Geo-Caching like ‘Citytag’ and hybrid reality games (HRG) like ‘Can you see me now?’, ‘I like Frank’, ‘Uncle Roy all around you’, ‘Pacmanhattan’ or ‘MOGI’ (cf. (Benford 2011)).

However, these mobile approaches suffer from shortcomings on various levels to really connect to architectural qualities and promote values in public space. First and foremost it should be realized that mobile phones and the application running on them in itself are creating a space. A second reality that concurrently creates, allows, and/or demands immersion, interaction and imagination. This means that attention is shifted from the real world to the virtual. The harmony between body, architecture and technology becomes shifted in favour of the (often) private and hidden virtual space. This means that, interaction designs of the mobile games tend to exclude or separate the player from the surrounding public life. This happens especially if the game demands continuous attention to be successful in the game. Furthermore, often these LBMG designs misjudge the bodily speed and energetic effort needed to move through space. Often these designs are thought at a scale of up to 1–3km (compare Figure 2).

However, other technologies than mobile personal computers have grown into the city and became an interest of Ubicomp research. Public displays, projections and media façades are technologies that can match the architectural scale and include the public life at the same time. They have furniture or even building size and provide a visual output at the same scale. This enables a public effect to be established because information is not hidden anymore, as was the case with a mobile phone. Putting issues of light pollution and attention grabbing content aside for the sake of constructively thinking about how to achieve harmony and grace between the body, technology and architecture we find the art form of façade mapping. An original technique fusing technology and architecture in a site-specific beautiful way by using the tactic of mapping (cf. (Urbanscreen)). However, this nowadays popular art form happening in our city has similar problems as the mobile games described by de Souza e Silva had (Silva/Hjorth 2009). It overwrites public space. In addition, the space becomes a cinema-like event, which ‘freezes’ public life for a moment (Figure 6). As a result, similarly to LBMG, separation among visitors is the effect even though the medium is visible to the public in contrast to the mobile phone. Balancing public life, technology and public space is a concern of Urban HCI (cf. (Urban Media Aesthetics)). Linking the bodily scale through technology to architecture without losing the aspect of public life turns out to be difficult.

In particular, one reason why balance is not achieved might be that the technological communication channel between human and architecture is underdeveloped in respect of interaction between both. Whereas today’s technology provides large scale displays in the form of bright projectors, high resolution LED matrices, lighting or motorized façade elements, the input channel is somewhat underrepresented. More interfaces need to be developed which support a many-to-many communication supported by architecture and technology. This balancing seems to happen now as we see more books like this one being published. While computer scientist’s lacked an understanding of space and created virtual spaces that detach people from the public space and bring them to an alternate one, architects found it hard to imagine how to gracefully integrate media technology into space. In the last ten years, both disciplines moved closer together; researchers from Ubiquitous Computing are starting to understand space at an architectural scale, public life and public space more and architects are starting to integrate interfaces to their designs (e.g. Behrens et al. (Behrens et al. 2014)) to balance out mono-directed communication channels of media architecture with novel interfaces.

At a pragmatic level for Urban HCI thinking,we propose to limit the scale at which it makes sense to attempt to balance public life, technology and built environment (architectural configurations) to a maximum of a 50 × 50 meter urban setting (compare Figure 2, bottom right). This is roughly the distance at which we found social interaction supported through Media Architecture can be achieved. It is also a distance at which the human senses to perceive each other still work well. In Jan Gehl’s book “Life Between Buildings” the social field of vision, as he calls it, is specified between 0–100m. At a distance of 100m human individuals can be seen. Between 70–100 m it becomes possible to determine with reasonable certainty a person’s approximate age, sex and what the person is doing (Gehl 2011, p. 65). To perceive people as individuals a much shorter distance of about 30 m is needed. Facial features, and hairstyle can be recognized and at 20–25 m feelings and moods of others become visible and relevant in a social context. All relevant features to be respected for a design of a lively or social situation. It also illustrates how ‘absolute’ measures of the body should be respected when designing space, whether being an architect or technologist.

From our experience with over 40 deployments of urban installations over the last seven years the 50 × 50 m situation is a good limitation to balance human activity, technology, and the environment, also because night time reduces the human senses (almost all of our media interventions only work in darkness as they used projection or similar) and technologies are also developed with limitations in range (e.g. WIFI, Pixel, etc.). From now, the term 50× 50 m urban setting refers to structures of the city (environment), which provide the space for the human activity (e.g. public life, interaction with the system, etc.). The term 50× 50 msetting includes the technical setup or ‘interactive system’ in addition to the environment and the 50× 50 m situation includes activity of the people in addition to environment and setup. The term marks the upper boundary of space at which we experienced a balancing of interaction to be feasible. Interaction for lager scales then moves towards crowd-computer interaction (see (Veerasawmy/Mccarthy 2014)) considering sizes of a football stadium (approx. 150–200 m) or neighbourhoods.

4Content and Values

In the prior section we have shown what scale the idea of Urban HCI focuses on. The recalibration of Ubiquitous Computing technologies to a street level is also a concern of the architect Malcolm McCullough, who, in his book “Digital Ground” (McCullough 2005) contrasts universal technology with situated technology as follows:

Tab. 1: Universal versus situated computing (McCullough 2005, p. 67).

In some respect, this comparison also summarizes the value technology creates in Ubiquitous Computing in contrast to Urban HCI. For the notion of Urban HCI and a better balance of public life, technology and built environment, the situated properties should guide new designs of interactive systems for public space. Conscious decisions regarding situatedness not only concern software and interaction design, but also interface design (physical form and hardware design). Much of Ubiquitous Computing seems to have adopted the notion of mobile phones as a universal interface.

Various HCI publications focus on the combination of the mobile phone and public displays or media façades: (Boring et al. 2011), (Martin et al. 2006), (Luojus et al. 2013), (Scheible/Ojala 2005), (Böhmer et al. 2011), (Gehring/Krüger 2012). However, the mobile phone interface disembodies valuable information situated in a public space. For example, BlogWall (Cheok et al. 2007) displays a user’s SMS in an animated manner and creates poetry from these. The authors describe this as “an extension of existing text messaging to a new level of self-expression and public communication using mobile phones and public displays.” and “… a step into new forms of cultural computing”. Although the designers of BlogWall found a smart way to create interesting content, the design stops short of thinking about the activity in front of the screen. Figure 5 shows the situation, which seems to separate the people in front of the screen by the use of the mobile. The social dynamics are shifted to an alternative space (the virtual). An interface, which is part of the physical space (e.g. a simple keyboard or touch-screen) would have created some activity around it and the social dynamics would have been more integrated into the environment. Using the mobile for this interaction design removes visible cues that provide opportunities to e.g. learn from a person or to provide fun or pleasure to watch for others. The disembodiment of information provided by an activity can be seen as reducing value for a public space. Even though the activity generated by BlogWall might be still visible and meaningful for bystanders, the reduction of information becomes more problematic at greater distances typical for urban settings.

The open question to ask is: Why should activity be visible? A part of the answer is already been given; “context is activity” (Table 1, right hand side). Without activity the system does not provide context. But this is important for a situation design, which aims to include people at a 50 × 50 m scale. From the urbanist William H. Whyte (Whyte 1988) we know that people like to watch other people and he names it the number one activity in public space. Furthermore, Carr et al. lists a number of passive engagements. For example, observing and viewing is named as providing values for public spaces (Carr et al. 1992, p. 320). They provide design recommendations for the needs of people in public places such as: “Good places to watch passing scene, people.”, “Overall views, well-framed vistas.” or “Good places to watch performers”. The idea of designing for observers has already been translated into HCI in Reeves’ account on “Designing the spectator experience” (Reeves et al. 2005) in public installations. Carr et al. (Carr et al. 1992, p. 320) also list values promoted by active engagement such as play, communication and discovery; general goals of making public space. How passive and active engagement and discovery can translate to HCI systems has been shown by Nemanja Memarovic et al. in (Memarovic et al. 2012). Thus, exposing context through activity might be a better design strategy for a 50 × 50 m situation than to conceal activity. Similarly, and to summarize in McCullough’s words, “architectural elements of physical space often frame and cue actions.” and Ubiquitous Computing should question the sufficient representation of action; “Who is present, and what are they trying to do?” (McCullough 2005, p. 100). In a situated design, values become embedded in physical structures such as places to socialize (eating, drinking, talking), places to meet (gathering), places for seeing and being seen (cruising), places for insider (belonging) (McCullough 2005, p. 120), etc.

Designing activity in a visible way can be used to create situations. This is one fundamental concept in Goffman’s studies of social interaction besides the two other central concepts of the social occasion and the gathering (encounter). In “Behaviour in Public Places” Goffman refers to a situation as a “full spatial environment anywhere within which an entering person becomes a member of the gathering that is (or does then become) present. Situations begin when mutual monitoring occurs, and lapse when the second-last person has left” (Goffman 1966, p. 18).

In Urban HCI this is the 50 × 50 m situation, which is to be designed. One value generated by a situation design, which goes beyond the design for the observer (Reeves et al. 2005) is based on Goffman’s concept of gathering (encounter). That is, “…any set of two or more individuals whose members include all and only those who are at the moment in one another’s immediate presence.” (Goffman 1966, p. 18). This definition has been extended to the concept of shared encounters. Defined by Willis et al. a shared encounter is “the interaction between two people or within a group where a sense of performative co-presence is experienced and which is characterised by mutual recognition of spatial or social proximity.” (Willis et al. 2010, p. 4).

The technological aspect for this concept is introduced by the definition of Ava Fatah gen. Schieck et al. “…a digital encounter is an ephemeral form of communication and interaction augmented by technology.” (Schieck et al. 2010, p. 180).

To give an example of a shared/digital encounter we refer to two very similar situation designs. In both situations public displays were evaluated in-the-wild. However, the installations had slightly different spatial interaction/interface designs, one using touch input (Behrens et al. 2013), and the other gestural input (Mueller et al. 2012).

While both provided interesting content for the users, the emerging activity constructs different situations. In the situation shown in Figure 7 (Behrens et al. 2013) the bystanders (2) and (5) have no opportunity to enter into immediate presence or co-presence (criteria of a shared encounter) with the performers (1). They need to wait to experience the installation (actively). Figure 8 shows a girl from group (A) noticing interactivity first, then woman (B) positions herself behind them to see what happens and also starts interacting, and later couple (C) starts to interact in a third row (Mueller et al. 2012). Even though they might not talk to each other, they experience an ephemeral form of communication produced through technology (digital shared encounter). This example shows space-making should also be a concern of designers of ‘interactive systems’. Creating co-awareness among strangers in an ephemeral social situation is certainly a valuable asset for the public space. The value is created within the encounter, not primarily through the content. Returning to the earlier discussion of the disembodiment of information with activity created by interfaces such as mobile phones (Figure 5), these two examples show in contrast a design of embodying information into activity, which might also provide more pleasure to watch for others, similar to a situation in Figure 6, where little stories by peoples’ activity within the fountain fog emerge. This also completes Goffman’s framework mentioned earlier. Installations like these can create social occasions, “this is a wider social affair […] bounded in regard to place and time. […] a social occasion provides the structuring of social context in which many situations and their gatherings [encounters; note by the authors] are likely to form, dissolve, and re-form, while a pattern of conduct tends to be recognized as the appropriate […]” (Goffman 1966, p. 18). Diffuse social occasions can develop a structure, for example be unserious, recreational, serious, regular, they can be looked forward to, looked back upon as a whole.

The public display example above also shows how a careful interface/interaction design (with visible activity) can have a self-reinforcing effect even though ‘only’ a public display application has been designed and not a full architectural configuration. Müller’s et al. (Figure 8) example demonstrated how one initial single performer can extend the situation and draw in others.

There are also greater implications to expect from a good situation design. For example, Tanenbaum’s sociological studies in the subways of New York (Tanenbaum 1995) showed that crime rates tend to go down in areas where buskers regularly perform. Situation designs that promote small forms of social encounters might have similar impact. Digital designs, which foster small-talk between strangers, sharing a playful experience or creating a social occasion to play, might have similar influence, a value for our cities worth to explore.

A Shared Encounter is only one concept posing a concrete value for public space. It is a measurable and countable phenomenon which can be provoked by carefully designed Media Architecture. However, to understand at an operational level how to construct such a phenomenon, it is necessary to understand spatial design as well as how ICT influences public live within that space.

5Summary and Conclusion

This chapter illustrated the granularity at which Urban HCI re-considers space as a resource for and product of new media artefacts in our city. It established an understanding of the difference between Ubiquitous Computing and Urban HCI by contrasting possible scales of mobile phone applications and the scale of the urban environment. To balance technology, public life, and architecture within the city, we proposed to focus on a max. 50 × 50 m situation, as it provides a scale at which this can be achieved on a practical level. Situations bigger than that tend to become mobile or distributed applications detached from the present setting. Creating a balance is a desirable endeavour to avoid an overwriting of urban places and segregating people as a result. However, there are also new strategies in the development, which might overcome the limitations of the 50 × 50 m situation. On a similar scale urban planning is operating, M. Hank Haeusler proposes in the following chapter an interaction paradigm based on the typology of the city. This provides the potential to bring ways of thinking of the architect and the computer scientist closer to each other. For architects it is abstracting from place and for creators of ICT it is reducing abstraction. This might lead to a common ground of developers and create distributed systems with an identity.

Urban design values such as providing vitality and stimulation for the dweller should lead the way. Urban design lists a plethora of ways how to increase the quality of a certain space (cf. (Carmona et al. 2010)), from which it is difficult to derive a specific direction as settings often have unique character difficult to code for as the complexity is too high and interpretation very subjective especially without formal architectural training. Here, William H. Whyte points to a valuable insight which provides focus: “People like to watch other people.” (Whyte 1988). We suggested to focus on the concept of shared encounters as a concrete value to enrich everyday life by design. In theory this could also lead to a measure of how valuable an ‘interactive system’ is, on the basis of how many shared encounters it produces. However, in the first place it has to be found out, what makes these shared encounters tick? While encounters have been explored in sociology by Goffman and other researchers, HCI currently explores how digital encounters might be produced and what types exist. Two examples of public displays showed how different interface/interaction designs create different situations with and without shared encounters happening. The reason seems to largely depend on the different spatial uses/designs of both installations and a self-reinforcing effect, where one activity sparks another activity to happen; extending a situation (sometimes also unintended). Thus the further focus of our research is directed toward understanding the ‘production’ of space through media interventions and the study of urban 50 × 50 m situations. With reference to Lefebvre, “If space is produced, our knowledge of it must be expected to reproduce and expound the process of production. The ‘object’ of interest must be expected to shift from things in space to the actual production of space […]” (Lefebvre 1991, p. 36f).