Purpose A systematic review was undertaken to characterize the training approaches that are currently being implemented in postgraduate medical education to teach residents advocacy skills. Method An initial search was conducted in MEDLINE, PubMed, Embase, ERIC, and PsycINFO in November 2016 (updated in December 2017) for articles discussing postgraduate medical education interventions covering advocacy. Articles published between 1995 and 2017 were included. Two authors independently reviewed titles and abstracts (and, if needed, the full text) for inclusion; disagreements were resolved by consensus. Data were extracted from studies to characterize the content and pedagogy of the interventions by mapping them to the CanMEDS health advocate core competencies and key concepts. Results A total of 3,027 unique abstracts were retrieved; 2,864 were excluded upon title and abstract review, and another 85 were excluded upon full-text review. Seventy-eight total articles were included. More studies involved residents from pediatrics, psychiatry, primary care or preventative medicine, or internal medicine than from emergency medicine, surgery, obstetrics and gynecology, or neurology. Published interventions varied widely by pedagogical approach and assessment method. Conclusions Using the CanMEDS framework, this review maps the breadth and nature of postgraduate medical education interventions in health advocacy, with applicability to community organizations, program directors, educators, and administrators working to develop advocacy training interventions. Areas of focus included adapting practice to respond to the needs of or advocacy in partnership with patients, communities, or populations served; determinants of health; health promotion; mobilizing resources as needed; and social accountability.