This ebook on mentoring relationships, which features some of the leading scholars in this field, offers new perspectives and frameworks suggesting exciting avenues for future research on mentoring and career development. In the last two decades, the workplace has been dramatically transformed. Individuals traditionally had careers entrenched in organizations, relying on the paternalistic firm for career development. Increasingly now, individuals are enacting careers outside of organizational boundaries, defining career success on their own terms rather than by the organizational measures of salary and rank. Rapid technological change and globalization has intensified the decoupling of individual careers from organizations, putting more emphasis on individuals for their own career development and creating an even greater need for mentoring. Although much research has been done on the impact of mentoring on subjective and objective career success, there are still many unexamined and under- explored aspects of mentoring. This collection of ten articles tackles some of these areas, providing new insights and offering new avenues for research and practice. These articles are authored by individuals from a variety of disciplines (e.g., organizational behavior, psychology, health care), and countries (e.g., US, UK, Nigeria), with each article bringing a unique lens to the study of mentoring and careers. Individually, each article makes a contribution to our better understanding of how mentoring has evolved and is enacted today. Together, this collection of articles provides important insights that we hope encourages even further research into the complexities of developmental relationships and their impact on career development.