Mark’s diverse entrepreneurial client base includes founders of transformative start-ups in technology, manufacturing, media, education, health care, finance, and marketing. His coaching skills and leadership development programs are engaged by C-level executives across all sectors of the economy, and his development of corporate and nonprofit boards allows them to govern more effectively. In the not-for-profit realm, he has consulted to and led leadership development initiatives for organizations ranging from multibillion-dollar philanthropic game-changers to local community-based social service providers to the world’s largest international NGOs. Much of his work to infuse progressive leadership practices into the NGO and not-for-profit world has been made possible by significant grants from the Ford, Rockefeller, Mott, and Charles H. Revson Foundations, among others.

A leading authority on Founders’ Dilemma, the strong and often dysfunctional psychological forces that organizational founders experience when they are pressured to step down, Mark has further advanced effective strategies for CEO transitions in the corporate and not-for-profit sectors. He continues to serve as a commentator on CEO personality and behavior across all media platforms.

Mark is a board member of Footsteps, a human rights organization that supports and affirms individuals and families who have left or are contemplating leaving, insular ultra-Orthodox Jewish communities in their quest to lead self-determined lives. He continues to serve on the board of Isabella Geriatric Center after three decades and was Board Chair for ten years. Isabella remains one of the largest not-for-profit continuum-of-care institutions in the Greater New York area.

Mark also serves on the board of MJHS Hospice and Palliative Care, as well as the Menorah Center for Rehabilitation and Nursing Care.