This chapter sets out the book's purpose, which is to explore the limits and potential of flexible working arrangements through the lived experience of women in professional and managerial jobs who adjusted their employment because of their motherhood. They include part-time, job-sharing, location-flexible, flexi-time working lawyers, doctors, academics, accountants, civil servants, bankers and senior managers in marketing, human resources, communications, research and technology, and they are all mothers of at least one infant or toddler, school-age child or teenager. The chapter discusses evidence which shows that there is a life and career stage when women tend to get stuck or get out of the pipeline to the top jobs in large organisations, and it corresponds with motherhood. The women whose experiences inform the research explored in this book are at that stage. They are women in the middle.