The purpose of this meta-analysis was to determine sample weighted mean validity effect sizes for occupational performance assessments, and their generalizability from research to clinical settings. The bare-bones Validity Generalization (VG) guidelines developed by Hunter and Schmidt ( 2004 ) augmented by Maximum Likelihood (ML) procedures were used to complete the meta-analysis. The sample consisted of 27 studies in which convergent, divergent, and predictive validity estimates of occupational performance assessments were investigated. The mean coefficients of assessments validated in the studies constituting the sample for this meta-analysis ranged from medium to large. Further meta-analysis with complete dis-attenuation of observed mean validity coefficients is indicated.