PURPOSE: Medication self-efficacy, or patients' confidence that they can perform medication-related behaviors, is associated with better glaucoma medication adherence. Little is known about how to enhance glaucoma patients' medication self-efficacy. Our purpose is to examine whether patient-provider communication increases glaucoma patients' medication self-efficacy. METHODS: During an 8-month cohort study of 279 glaucoma patients and 15 providers, two office visits were videotape-recorded, transcribed, and coded for six patient-provider communication behaviors. A validated scale was used at baseline and 8-month follow-up to assess patients' confidence in overcoming adherence barriers (adherence barriers self-efficacy) and carrying out tasks to use eye drops correctly (eye drop task self-efficacy). We ran two generalized estimating equations to examine whether more frequent patient-provider communication during office visits predicted increased patient adherence barriers self-efficacy and eye drop task self-efficacy at 8-month follow-up. RESULTS: For each additional topic providers educated about, patients reported an average increase of 0.35 in self-efficacy in overcoming adherence barriers (p < 0.001). Patients also reported an average increase of 1.01 points in eye drop task self-efficacy when providers asked about patients' views of glaucoma and its treatment versus not (p < 0.001). Patients who asked more medication questions (p < 0.001) and African-American patients (p < 0.05) reported lower adherence barriers self-efficacy by 0.30 and 2.15 points, respectively. Women had a 0.63 lower eye drop task self-efficacy than men (p < 0.05). CONCLUSIONS: When providers educate glaucoma patients and assess patient views about glaucoma and its treatment, patients report higher medication self-efficacy. Providers should be aware that patients who ask more medication questions may have less confidence in their ability to overcome barriers to adherence.