Writing this book has given me great satisfaction in being able to share my knowledge and experience about a subject I am very passionate about; in many ways it marks the culmination of many years of study and professional experience. To this end, I must thank all those who have supported and encouraged me through the years – too many to mention individually, but I include teachers, friends, family and professional colleagues. A special tribute goes to my parents, who have been unshakeable in their unconditional love and support throughout my life and worked tirelessly to give me the best possible foundation in life; also a special thanks to my wife, Tassnima, my children – Emaan, Mustafa and Misbah and my siblings – Shamim, Merunisha, Salma and Arif for their love, support and help over the years.