Penicillin resistance amongst gonococcal strains causing disseminated gonococcal infection (DGI) has been infrequently reported worldwide. The clinical records of 34 patients with gonococcal arthritis seen over a 53-month period were reviewed. The study population consisted of 32 blacks and two Indians with a mean age of 23.5 yr (range 14-46 yr) and a female to male ratio of 2.8:1. The diagnosis of gonococcal arthritis was made on the basis of isolation of Neisseria gonorrhoeae from the SF alone in 20 patients, SF and genital site in nine genital site alone in two and genital site and synovial tissue in one patient and synovial tissue alone in two patients. Eighteen of the 32 (56%) synovial isolates were penicillinase-producing strains of N. gonorrhoeae (PPNG). Monoarthritis was the commonest mode of presentation and seen in 73% of patients. The joints most frequently involved were the wrist (44%), knee (41%), ankle (15%) and shoulder (12%). None of the patients had cutaneous lesions. The occurrence of DGI is usually associated with protein 1-A serotype and arginine, hypoxanthine and uracil requiring auxotype, but all isolates available for auxotyping in this study were prototrophic. This study shows a very high prevalence of PPNG strains causing DGI, an observation which has important therapeutic implications.