The literature on benign transient lymphangiectasis of the penis (BTLP) was reviewed; reports of 45 cases were collected and a further series, comprising 21 cases, is presented. Both the published and present series support the view that BTLP is associated with recent sexual activity; little support is given for an infective cause and it is confirmed that BTLP is a benign, self-limiting condition presenting in the sexually active man between 20 and 40 years old. There can be recurrences, and susceptibility to them may be encouraged by circumcision in which disturbances of lymphatic drainage may play a part. As so few cases have been reported and few were diagnosed in the present series these comments can only be pointers to further studies. The descriptions in six histological examinations, the reports as `phlebitis' of apparently similar lesions, the report of `sclerosing lymphangitis' in other sites, and the known histological similarity between veins and lymphatics suggest that `sclerosing lymphangitis' is too specific a term. Until further knowledge is available, we suggest that this condition is best regarded as simple dilatation of a lymphatic vessel—namely, lymphangiectasis. As the condition is both benign and transient we propose the term benign transient lymphangiectasis of the penis for the condition formerly known as sclerosing lymphangitis.