Hospitalized older adults are susceptible to complications termed “hazards of hospitalization” (HOH), which collectively result in poor patient outcomes. Previous research has shown that residents are not aware of their patients' risk factors for HOH. This study investigated the effect of an educational intervention to increase internal medicine interns' knowledge and self-efficacy of HOH and to improve their care of hospitalized older adults as measured by their documentation of HOH. Targeted learners were internal medicine interns on their geriatrics rotation at a large academic hospital in 2011 to 2012. The intervention covered 10 specific HOH: delirium, pressure ulcers, urinary incontinence and retention, functional decline, falls, suboptimal prescribing, dehydration and malnutrition, infection, depression, and inappropriate interventions. Knowledge and self-efficacy were measured before and after training. HOH documentation rates of interns who did and did not complete the training were compared over a preset 8-week period. Forty-two of 43 eligible interns completed the curriculum. After training, knowledge was significantly greater (approximately 1 more correct question out of 3, P < .001). Self-reported confidence in managing each hazard also significantly increased (13 questions on two 5-point Likert scales, P < .001). Trained interns had significantly more-frequent documentation of patients' activities of daily living, gait, and plan for functional decline prevention than interns who were not trained (P < .05). Conversely, documentation of instrumental activities of daily living was more frequent among interns who were not trained (P < .01). Implementation of an educational intervention was successful in improving educational and behavior change outcomes regarding HOH.