The purpose of this qualitative study was to elicit information on why a promotora (or, community health worker (CHW)) increased adherence to chronic disease screening among women along the U.S.-Mexico border. After completion of the intervention, women and clinic staff who participated in the promotora phase of a randomized, controlled study answered structured, open-ended questionnaires. Clinicians from two non-participating clinics were also interviewed. Content analysis found that the promotora's roles included health education and the facilitation of routine and follow-up care. Clients appreciated the promotora's socio-cultural characteristics, as well as her personal skills and qualities, and described her as a trained, natural helper whose personalized support removed barriers to health care and helped women to take care of themselves. Most clinicians recommended working with a CHW to increase adherence to chronic disease prevention practices. A CHW can play a crucial role on a health care team and interventions should tap into this resource.