Chastain has been working in international health for 25 years, with more than 10 years of that time implementing programs in sub-Saharan Africa. A former Foreign Service Officer, Chastain has worked for bilateral and multi-lateral agencies, as well as for large and small non-profits. In her 11 years at Population Services International (PSI) Chastain served as the country director in Togo and Uganda, where she designed and implemented social marketing and franchising programs in HIV, reproductive health, malaria, and child survival. In each place, with a team of more than 100 local staff, Chastain developed marketing and communications strategies for health products and services, as well as monitoring and evaluation, sales and distribution, franchising, and advocacy approaches. As PSI’s VP for Strategic Partnerships and Business Development, Chastain led a team that created fund raising strategies to raise more than $4 billion over 6 years.

More recently, Chastain worked with Woman Care Global as President of Programs, where she led fund raising efforts as well as program implementation, with a focus on improving the value chain for reproductive health commodities. Chastain’s inspiration for starting Mann Global Health was to bring together some of the world’s leading experts in measurable, effective health programming, and share their talents with global health clients.