Mentoring has become increasingly important as a mode of professional development in education. Mentoring has grown in importance in England and Wales, partly as a result of the shift to self-management in schools and colleges. There is a growing recognition that organisational performance depends critically on the selection, development and motivation of staff. The concept of socialisation was not considered important to the understanding of mentoring, and where mentors and new heads recognised socialisation as part of the relationship, it was narrowly interpreted as the introduction of the new headteacher to others in the area, who might prove to be useful contacts. The research reported in this chapter relates to three important stages of professional development in education. Most teachers subsequently take on additional responsibilities, perhaps as heads of departments or subject co-ordinators, and mentoring may be valuable as new and unfamiliar tasks are added to the core classroom role.