SETTING: In March 2006, the first multidrug-resistant tuberculosis (MDR-TB) treatment programme was implemented in Kenya. OBJECTIVE: To describe patients' treatment outcomes and adverse events. DESIGN: A retrospective case note review of patients started on MDR-TB treatment at two Medecins Sans Frontieres-supported sites and the national referral hospital of Kenya was undertaken. Sites operated an ambulatory model of care. Patients were treated for a minimum of 24 months with at least 4-5 drugs for the intensive phase of treatment, including an injectable agent. RESULTS: Of 169 patients, 25.6% were human immunodeficiency virus (HIV) positive and 89.3% were culture-positive at baseline. Adverse events occurred in 67.4% of patients: 45.9% had nausea/vomiting, 43.9% electrolyte disturbance, 41.8% dyspepsia and 31.6% hypothyroidism. The median time to culture conversion was 2 months. Treatment outcomes were as follows: 76.6% success, 14.5% deaths, 8.3% lost to follow-up and 0.7% treatment failure. HIV-positive individuals (adjusted odds ratio [aOR] 3.51, 95% confidence interval [CI] 1.12-11.03) and women (aOR 2.73, 95%CI 1.01-7.39) had a higher risk of unfavourable outcomes, while the risk was lower in those with culture conversion at 6 months (aOR 0.11, 95%CI 0.04-0.32). CONCLUSION: In Kenya, where an ambulatory model of care is used for MDR-TB treatment, treatment success was high, despite high rates of HIV. Almost half of the patients experienced electrolyte disturbance and one third had hypothyroidism; this supports the view that systematic regular biochemical monitoring is needed in Kenya.