A retrospective chart review study was conducted to evaluate health outcomes after a nurse-led short-term medical mission group provided free health care in four communities in Kingston, Jamaica over a four-year period. Participants were adult patients who had visited short-term medical mission clinics at least twice and were diagnosed with hypertension and/or diabetes. Blood pressure (BP) and blood sugar (BS) results along with factors including adherence and control per guidelines were analyzed using descriptive, t-tests and chi-square analysis. The data revealed that overall BP and BS measurements trended down, and there was a significant decrease in BP in patients with uncontrolled hypertension at the first visit. Medication adherence between the visits and gender had a statistically significant impact on BP and BS control. Outcomes suggest short-term medical missions are an effective model to address hypertension and diabetes in developing countries when using a sustainable approach.