Sclerotherapy with 3% sodium tetradecyl sulfate and 3.5% rolitetracycline on an outpatient basis was applied to 55 hydroceles. The over-all cure rate was 96% with an average followup of 13 months. Of the patients 64% were cured after only 1 sclerosant instillation. A post-sclerotherapy operation was necessary in 4% of the patients. Pain of a significant degree occurred after sclerotherapy in only 29% of the patients. Sclerotherapy appears to be an effective, economical and safe form of outpatient therapy for hydroceles.