A continuous assessment and a categorical diagnosis of the presence of mental health, described as flourishing, and the absence of mental health, characterized as languishing, is applied to a random sample of 1050 Setswana-speaking adults in the Northwest province of South Africa. Factor analysis revealed that the mental health continuum–short form (MHC–SF) replicated the three-factor structure of emotional, psychological, and social well-being found in US samples. The internal reliability of the overall MHC–SF Scale was 0.74. The total score on the MHC–SF correlated 0.52 with a measure of positive affect, between 0.35 and 0.40 with measures of generalized self-efficacy and satisfaction with life, and between 0.30 and 0.35 with measures of coping strategies, sense of coherence, and community collective self-efficacy. The total score on the MHC–SF correlated −0.22 with the total score on the General Health Questionnaire. Criteria for the categorical diagnosis were applied, and findings revealed that 20% were flourishing, 67.8% were moderately mentally healthy, and 12.2% were languishing. Confirmatory factor analysis supported the hypothesized two continua model of mental health and mental illness found in the USA.