['HIV infection is clinically managed with antiretroviral therapy (ART), but only with sustained adherence. Cost-efficient interventions to improve and sustain ART adherence remain a pressing priority for populations challenged by nonadherence. The aim of this study was to test the independent and interactive effects of (1) brief phone-delivered self-regulation counseling and (2) daily phone-delivered text message medication reminders on HIV adherence and HIV viral suppression.', 'A randomized 2 (5 sessions of phone-delivered adherence support counseling vs. contact-matched control) × 2 (daily ART text reminders vs. no reminders) trial with primary end points of monthly phone-based unannounced pill count-determined ART adherence and HIV viral suppression monitored over 12 months.', 'Self-regulation adherence counseling demonstrated significant improvements in achieving 90% ART adherence relative to the control group over the first 6 months of follow-up. Effects remained significant in sensitivity analyses conducted at 85% and 95% adherence. Counseling also demonstrated modest but significant effects on HIV suppression. There were no main effects or interactions for daily text message reminders, with some evidence for adverse effects on adherence self-efficacy.'] Do randomized Factorial Trial of Phone-Delivered Support Counseling and Daily Text Message Reminders for HIV Treatment Adherence?