In Appreciation of Adam: Reflections from Friends and Colleagues.

Some of Adam Wagstsaff's colleagues and research collaborators submitted short reflections about the different ways Adam made a difference through his amazing research output to health equity and health systems as well as a leader and mentor. The Guest Editors of this Special Issue selected a set of six essays related to dimensions of Adam's contributions.The first contribution highlights his role early on in his career, prior to joining the World Bank, in defining and expanding an important field of research on equity in health ("Adam and Equity," by Eddy van Doorslaer and Owen O'Donnell). The second contribution focuses on Adam's early work on equity and health within the World Bank and his leadership on important initiatives that have had impact far beyond the World Bank ("Adam and Health Equity at the World Bank," by Davidson Gwatkin and Abdo Yazbeck). The next contribution focuses on Adam's deep dive into providing support, through research, for country-specific programs and reforms, with a special focus on some countries in East Asia ("Adam and Country Health System Research," by Magnus Lindelow, Caryn Bredenkamp, Winnie Yip, and Sarah Bales). The next contribution highlights Adam's many ways of contributing to the International Health Economics Association, from the impressive technical contributions to leadership and organizational reform ("Adam and iHEA," by Diane McIntyre). The next to last contribution focuses on Adam's long-term leadership in the research group at the World Bank and the long-lasting influence on integrating the research produced into World Bank operations and creating an environment that rewarded producing evidence for action ("Adam the Research Manager," by Deon Filmer and Damien de Walque). The last contribution pulls on the thread found in many of the earlier ones, mentorship with honesty, directness, caring, commitment, and equity ("Adam the Mentor," by Agnes Couffinhal, Caryn Bredenkamp, and Reem Hafez).