A nursing clinic for homeless men was developed by a faculty member and her senior community health nursing students in a city mission over a 2.5-year period. The development of this clinic and a conceptualization of their nursing roles are described. Nursing care focused on promoting access to primary care through screening and referral and through nursing interventions of education, counseling, advocacy, and collaboration. Because the Student Nurses' Clinic was instrumental in clarifying and conceptualizing what nurses can do to promote primary care, mission administrators and staff gained insights about nursing and are better prepared to plan programs for the health care needs of the homeless men-the "guests" at the mission.