Tim’s training ground was the Population Council, a premier international non-profit, non-governmental institution that conducts biomedical, public health, and social science research, helping to build research capacities in developing countries. He joined the Council in 1991, and was promoted to play a leading role in external relations, public affairs, and fundraising. During his tenure, the Council’s unrestricted funding from foreign governments increased by 132%, and new funding schemes were established with the Governments of Japan, New Zealand, and the U.K. He also served as the primary point of contact with the international NGO community and with the U.S. Government, managing the Council’s $13 million co-operative agreement with the U.S. Agency for International Development. 

From 1998-2001, Tim was a senior consultant at the London-based communications agency InterScience, working with a range of clients on their sexual and reproductive health programs. When InterScience folded in 2001, he continued consulting privately. By analyzing policy trends, programmatic developments, donor priorities, and a vast range of research, he helped clients shape their communications programs, fundraising strategies, and address their organizational development needs.  Some of his major clients were the Rockefeller Foundation, the International Council of AIDS Service Organizations; the International AIDS Vaccine Initiative; the International Partnership for Microbicides; the Guttmacher Institute; GlaxoSmithKline’s Positive Action program and GSK Biologicals. 

In April 2006, Tim was appointed Executive Director of the Staying Alive Foundation at MTV Networks International based in New York.  A global grant-making and advocacy organization, the Foundation encourages and enables young people who are involved in HIV and AIDS awareness, education and prevention campaigns.  When MTV changed its philanthropic directions, Tim returned to private consulting. 

In late 2008, The Bill and Melinda Gates Foundation awarded a $12m, 3-year grant to launch The Maternal Health Task Force, and the CEO of its host NGO (EngenderHealth) called in Tim to spearhead the process of turning the proposal into a project.  Starting with public announcements and events throughout the global public health world using an array of interpersonal and electronic communications vehicles, soon the MHTF was ensconced as a vital convening, coordinating and catalyzing entity in the maternal health field.  When the MHTF moved to the Harvard School of Public Health In 2011 with an increased Gates grant and several other major donors including the MacArthur Foundation, Tim continued as Senior Advisor on a broad range of communication and policy projects.

From 2014-2016, Tim was a Senior Program Officer at the Gates Foundation.  His portfolio spanned the continuum of sexual, reproductive, maternal, newborn, child and adolescent health policy and communication with grants at the global and country levels.  Starting in 2017, Tim re-launched his consultancy, "timothythomasdotnet" where he continues his work to improve the health and well-being of women and girls everywhere. 

Tim is a long-time resident of New York City and has traveled extensively in Africa, South Asia and Europe. He pursues a lifelong goal of fluency in French and Italian, and studies classical singing. He graduated with honors from the Interlochen Arts Academy; he holds a Bachelors of Arts degree from Iowa State University and a Masters of Fine Arts degree from New York University.