The extent to which psychopathy can be reliably assessed via self-report has been debated. One step in informing this debate is examining the internal consistency of self-report psychopathy measures, such as the Triarchic Psychopathy Measure (TriPM; Patrick, 2010). Reliability generalization (RG) studies apply a meta-analytic approach to examine the internal consistency of an instrument in a more robust manner by aggregating internal consistency statistics reported across the published literature. This study conducted an RG analysis to yield the average Cronbach's alpha among published studies (k = 219) that administered the TriPM. Meta-analytic alphas were high for TriPM Total (α = .88) Boldness (α = .81), Meanness (α = .87), and Disinhibition (α = .85). Moderator analyses indicated internal consistency differed minimally as a function of study characteristics, like gender, age, or the nature of the sample (i.e., forensic or community). Subsequent RG analyses were performed for McDonald's omega (k = 40), which yielded comparable internal consistency estimates. The results of this study provide strong evidence that the TriPM measures coherent, internally consistent constructs and thus could be a viable, cost-effective mechanism for measuring psychopathy across a broad range of samples.