The 'oil' obtained from emu fat can be a very effective inhibitor of chronic inflammation in rats when applied dermally (with a skin penetration enhancer). Assays for this activity using the adjuvant-induced arthritis model have shown: i. Considerable variability in potency of some commercial oil samples; ii. Little or no correlation of activity with colour or linolenic acid (18:3) content of the oil; iii. Relative stability of some active oils (to heat, ageing at room temperature); iv. The bulk of the anti-inflammatory activity was present in a low triglyceride fraction; and v. Potential arthritis-suppressant/immunoregulant activity of these active fractions. These studies point to the need for more rigid quality control before considering such a (now proven) traditional medicine as a complementary therapy.Repeated applications of selected oils did not induce any of the more prominent side-effects associated with NSAIDs (e.g. platelet inhibition, gastrotoxicity) or certain anti-arthritic drugs (proteinuria, leukopenia).