The relationships between health and job performance problems have received increased attention in business and scientific communities. This paper attempts to synthesize theoretical and empirical work in this arena. First, the theoretical links between health and work performance are presented. This is followed by a meta-analysis of the relations between psychological, physical, and behavioural health variables and work performance criteria. Meta-analytic results from 111 independent samples obtained from a search of the literature indicate that psychological health, in the form of psychological well-being, depression, general anxiety, and life satisfaction, is a moderate-to-strong correlate of work performance. Associations between physical health, particularly somatic complaints and hypertension, and performance were weak-to-moderate. Regarding health behaviour, alcohol consumption, and smoking were weakly and sleep problems moderately associated with performance problems. Effect sizes sometimes differed across performance dimensions and data sources. The results are consistent with the notion that ill-health is associated with substantial reductions in work performance. This implies that interventions to improve health may have an impact on performance. However, as most of the research in this area has been cross-sectional, more longitudinal research is needed to test theoretical and alternative causal explanations for the relations summarized in this review.