Purpose: Practicing physicians have a societal obligation to maintain their competence. Unfortunately, the self-regulated learning skills likely required for lifelong learning are not explicitly addressed in most medical schools. The authors examined how medical students' perceptions of the learning environment relate to their self-regulated learning behaviors. They also explored how students' perceptions and behaviors correlate with performance and change across medical school. Method: The authors collected survey data from 304 students at different phases of medical school training. The survey items assessed students' perceptions of the learning environment, as well as their metacognition, procrastination, and avoidance-of-help-seeking behaviors. The authors operationalized achievement as cumulative medical school grade point average (GPA) and, for third- and fourth-year students, collected clerkship outcomes. Results: Students' perceptions of the learning environment were associated with their metacognition, procrastination, and help-avoidance behaviors. These behaviors were also related to academic outcomes. Specifically, avoidance of help seeking was negatively correlated with cumulative medical school GPA (r = -0.23, P < .01) as well as exam (r = -0.22, P < .05) and clinical performance (r = -0.34, P < .01) in the internal medical clerkship; these help-avoidance behaviors were also positively correlated with students' presentation at a grade adjudication committee (r = 0.20, P < .05). Additionally, students' perceptions of the learning environment varied as a function of their phase of training. Conclusions: Medical students' perceptions of the learning environment are related, in predictable ways, to their use of self-regulated learning behaviors; these perceptions seem to change across medical school.