A cell wall-defective form of Neisseria gonorrhoeae from an exudate of an untreated patient with gonococcal urethritis was isolated on medium containing 7% polyvinylpyrrolidone. Initial attempts to grow the organism by standard microbiological methods had failed. This isolate was incapable of reversion to a normal gonococcus even after numerous subcultures and appeared to be a stable cell wall-defective form.