SummaryProtein binding of urate may have some pertinence to the pathogenesis of goat. However, binding studies have been hampered by problems within vitromethodology and by the problem of relating the results ofin vitrostudies to the physiological situation.In the present study urate binding was determined by an ultrafiltration procedure. All manipulations were performed anaerobically and at 37° in order to maintain the sample under physiological conditions.Normal urate bound was 15 ± 7·5% in males and 10 ± 6·67 in females. Urate binding did not correlate significantly with either the albomuin or total urate concentration. It is suggested that the interaction between protein and urate is influenced by a number of factors other than the concentrations of free urate and binding protein. Some possible ones are discussed.The techniques described might usefully be applied to a study of urate binding in various pathological states.