INTRODUCTION AND METHODS: Information from myasthenia gravis (MG) patients treated and evaluated for at least 2 years between 1980 and 2014 was reviewed to assess the effect of demographics, antibody status and titer, thymus histology, and clinical severity on outcome after 2, 5, and 10 years of treatment. RESULTS: Among 268 patients, 74% had acetylcholine receptor antibodies, 5% had muscle specific tyrosine kinase-antibodies, and 22% had neither. Optimal outcome was achieved by 64% of patients at 2 years of follow-up, 73% at 5 years, and 75% after 10 years. Optimal outcome was achieved more often in patients with late onset, in those who had thymectomy, and in those with ocular-only disease at maximum severity. The only consistent independent predictor of optimal outcome was onset after age 50 years on multivariate analysis. CONCLUSIONS: Prognosis is favorable for the majority of MG patients, regardless of age, maximum disease severity, or antibody status. Muscle Nerve, 2016 Muscle Nerve 54: 1041-1049, 2016.