The Malawi Longitudinal Study of Families and Health (MLSFH) is one of very few long-standing publicly-available longitudinal cohort studies in a sub-Saharan African (SSA) context. It provides a rare record of more than a decade of demographic, socioeconomic and health conditions in one of the world's poorest countries. With data collection rounds in 1998, 2001, 2004, 2006, 2008, 2010 and 2012 for up to 4,000 individuals, the MLSFH permits researchers to investigate the multiple influences that contribute to HIV risks in sexual partnerships, the variety of ways that people manage risk within and outside of marriage, the possible effects of HIV prevention policies and programs, and the mechanisms through which poor rural individuals, families, households, and communities cope with the impacts of high morbidity and mortality that are often---but not always---related to HIV/AIDS. The MLSFH been used to document (i) the influence of social networks on HIV-related behaviors and perceptions, (ii) the HIV prevention strategies employed by individuals in rural high-HIV prevalence contexts, (iii) the relationship between life-course transitions and HIV infection risks, (iv) the acceptability of HIV testing and counseling (HTC) and the consequences of HTC on subsequent behaviors, and (v) the health and well-being across the life-course of individuals facing multiple challenges resulting from high disease burdens and widespread poverty.