The concentrations of creatine (Cr), phosphorylcreatine (PCr) and creatinine (Cn) were determined in a variety of meats, before and after cooking by boiling, in a range of commercially available canned dog foods, in rendered and dried meat products and in commercially available dry dog foods. None of the samples contained PCr. Uncooked chicken, beef and rabbit meat contained approximately 30 mmol kg-1 of Cr. Ox-heart and ox-liver had Cr concentrations of 22.5 and 2.3 mmol kg-1, respectively. Canned dog foods had Cr concentrations of 0.5 to 2 mmol kg-1. Dried meat samples had Cr concentrations of 90 to 100 mmol kg-1 dry weight. In contrast, the Cr concentration of dried rendered meat meal was 3 mmol kg-1 dry weight or less. Dry dog foods contained 0.5 to 4 mmol kg-1 dry weight of Cr. The results indicate that in the canned dog foods, the dried meat samples and the dried rendered meat meal creatine had been degraded to variable extents to creatinine.