In 1965, Bruce Tuckman published a paper Developmental Sequence in Small Groups in the Psychological Bulletin, Volume 63, Number 6, Pages 384-99.

In it, he described four stages of group development:

1. Forming: The getting to know you phase, where our team finds out more about each other and about their mission
2. Storming: A phase of conflict during which our team challenges assumptions about how we are going to work together
3. Norming: Differences are ironed out, and a consensus is reached, and then the team begins to work as one
4. Performing: Team practice and process improvements along with a better understanding of how the problem will be solved; all work together to create a profound shift in the team dynamic and its likelihood of success

The following diagram shows the stages of team development represented visually:

• Adjourning: Tuckman later added a fifth stage, adjourning; this reflects the period a team transitions during its disbandment. Sometimes also known as mourning, depending on how close-knit the group has become and how invested they were in their current workstream.

The important aspect of team development to understand is, regardless of how experienced individual members are any team that is newly formed or has approximately 50% of its membership changed will go through these stages to one degree or another.

In the following sections, we'll look at each stage, how this relates to our team, what we might encounter, and what we can do to help them progress to the next phase of development.

Remember, these are more of a topic for conversation with our team to help them understand what is happening and to provide some useful activities that will hopefully help them engage proactively with each other. 

Don't use Tuckman's model to try to put our team into a box, it won't help them progress. Instead, accept that they may be in multiple boxes at once. Look for signs and symptoms and facilitate the conversation.

Sometimes a team will take big leaps forward, for example, they may bypass the storming stage entirely. Sometimes they may take one step forward and two steps backward.