From February 1971 through February 1989, 51 patients with biopsy proven epidermoid carcinoma of the penis were treated with interstitial therapy (Iridium 192). The breakdown according to the stage was T1s = 3, T1 = 14, T2 = 28, T3 = 6, N0 = 43, N1 = 7, N2 = 1. The dose ranged from 50 to 65 Gy (mean: 60 Gy). Patients without clinical nodal involvement received no treatment to the nodes. Stage N1 and N2 patients had surgery and external irradiation to the inguinal and iliac nodes. Six of fifty-one (12%) patients developed nodal and/or metastatic disease following therapy. Five of six presented initially with clinical nodal involvement. Seven of fifty-one (14%) developed local recurrence only, requiring surgery (four partial penectomies, three total penectomies). Six of these seven patients are alive and free of disease with a mean follow-up of 5.5 years. Nine of thirty eight (23%) patients with local control developed local necrosis. The treatment consisted of local excision (one patient), partial amputation (six patients) or total amputation (two patients). Partial urethral stenosis was noted in 17/38 (45%) of the patients. Foreskin sclerosis occurred in 3/38 (8%) uncircumcised patients. Interstitial irradiation for penile carcinoma provided effective local control rates, especially for T1-T2 patients (91%). Local failures could be treated successfully with surgery. Complications could be treated conservatively in most patients. Local control with penile conservation was achieved in 67% of all patients and 75% of patients with T1-T2 disease.