Dr. Riddle has written extensively about diasporas and development, international entrepreneurship, and trade and investment promotion. She co-authored the first published study about diaspora investment in the Journal of International Business Studies in 1999. Having examined diaspora investment and entrepreneurship for over 25 years, Dr. Riddle has conducted research with diaspora communities in the USA and Europe originating from countries of origin in Africa, Asia, the Caribbean, Europe, Latin America, and the Middle East. Since 2006, she has led the GW Diaspora Capital Investment Project, which generates and disseminates learning about diaspora investment and its role in development to assist private-sector firms, policymakers, diaspora organizations, diaspora entrepreneurs, and researchers.