BACKGROUND AND OBJECTIVES: Although many curricular and policy interventions are designed to influence students’ attitudes toward family medicine, assessment of these interventions is limited by lack of a comprehensive, validated measure of students’ attitudes. We sought to develop and validate a questionnaire that effectively assesses medical student attitudes toward family medicine. METHODS: A 31-item questionnaire was assessed for internal, external, and content validity. The questionnaire was offered to fourth-year students at two Midwestern medical schools. Internal validity was assessed using data reduction and iterative factor analyses. External validity was assessed by correlating scores with intention to match in family medicine. Content validity was assessed by directly observing students as they completed the questionnaire and qualitatively evaluating student comments. RESULTS: Of 858 students invited, 426 (49.7%) provided usable questionnaire data. After removal of questions with lower interitem correlations and simplification of subscales, the modified questionnaire achieved acceptable subscale internal consistency and a Cronbach alpha of 0.798. The overall instrument summative score correlated with family medicine career choice (P<0.001). Most subscales and individual items also correlated with family medicine choice. Ten students were directly observed, using an iterative process, and modifications were made based on student understanding. CONCLUSIONS: Development of a validated questionnaire assessing medical student attitudes toward family medicine is feasible. With further refinement, the Family Medicine Attitudes Questionnaire may be useful in evaluating the impact of curricular interventions on students’ perceptions of family medicine, contributing to an evidence-based approach to recruitment of students to the specialty.