The arginine-hypoxanthine-uracil auxotype has been linked with the propensity of gonococci to cause disseminated infections. Gonococci recovered from 25 patients with disseminated gonococcal infections were compared with gonococci recovered from matched controls, patients with uncomplicated gonorrhea selected during the same month. Minimal inhibitory concentrations of penicillin, tetracycline, crythromycin, and ampicillin, and the nutritional requirements (auxotypes) for prolinc alone, arginine alone, arginine, hypoxanthine and uracil together, serine alone and cysteine-cystine (wild type) were analyzed by discriminant analysis. Significant susceptibility to penicillin characterized strains causing disseminated infections, and a proline requirement was the most common auxotype (48%) among strains isolated in Atlanta. Together the minimal inhibitory concentration of penicillin and the proline auxotype best separated the strains causing disseminated gonococcal infections from those causing gonorrhea. The arginine-hypoxanthine-uracil auxotype was found in only 24% of strains causing disseminated infections. A trait other than auxotype must determine the capacity of the organisms to disseminate.