Objective: To examine whether theories and/or models are used in interventions geared towards improving health-related outcomes for individuals with limited literacy skills. Methods: Intervention studies (n = 52) published between 1980 and 2009 that met inclusion criteria were reviewed to assess the topic addressed, type of theory and/or model used, and the extent of theory use. Results: Twenty-one (40.4%) interventions were based on a theory or model. Most of those 21 interventions were either "informed by" (n = 15, 71.4%) or "applied" (n = 4, 19.1%) theory whereas 2 (9.5%) "tested" theory. Conclusions: Most low-literacy intervention research is not based on any educational, behavioral, or social science theory or model.