 Retaining HIV-infected patients in care is critical, but loss to follow-up after enrolment often reaches 20-40 by two years, placing millions of patients at risk of poor outcomes. A strategy to optimize retention within resource constraints is urgently needed. Sequential adaptive strategies - a novel class of public health approaches - may offer a solution. A candidate sequential adaptive strategy would start with a less expensive intervention e.g., SMS in all patients and then apply a more costly and intensive one e.g., navigator only to patients who show early signs of poor retention. This study involves a sequential multiple assignment randomized trial to evaluate a family of such strategies. the investigators will randomize 1,800 adults newly initiating antiretroviral treatment ART at 4 HIV clinics in the Nyanza region of Kenya to 1 standard of care routine education and counselling REC, 2 SMS text messages, or 3 transport vouchers. Patients with early signs of weakening retention defined as the first time a patient is 14 days late for an appointment will be re-randomized to 1 a single episode of outreach standard of care, 2 SMS combined with vouchers, or 3 a peer navigator. Patients not successfully contacted by 28 days after missed visit and not verified to have left the area or transferred to another clinic will also be rerandomized to of one the same three re-engagement interventions. Individuals randomized at first stage to SMS or voucher that do not miss a visit by at least 14 days in the first 12 months of follow up will be re-randomized at 12 months to stop first stage intervention or continue with that same intervention to 24 months. The investigators primary objective is to assess the comparative effectiveness of sequenced intervention strategies to prevent initial lapses in retention and to treat those that occur. The investigators primary endpoint is fraction of time retained in care two years after enrolment. In addition, the investigators will assess the comparative effectiveness of first-stage strategies REC, SMS, voucher to prevent lapses in retention, and the comparative effectiveness of second stage strategies outreach, SMS voucher, navigator to re-engage patients after initial lapse. This study will also compare outcomes among patients who continue versus discontinue the SMS and voucher interventions, including a small complementarity component utilizing qualitative methods to examine the voucher approach and the effects of discontinuing this approach after success among a subset of participants. At study conclusion the investigators output will be a menu of adaptive strategies for retention, accompanied by estimates of cost and effectiveness, which policy makers in different settings can use to advance the impact of HIV care and treatment programs in Africa. 