The proctologist is above all concerned with the known recrudescence of venereal diseases. Examples reviewed are diseases of bacterial origin (syphilis, gonorrhea, soft chancre, donovanosis and chlamydiosis), appropriate antibiotic therapy and diseases of viral origin (herpes, condyloma acuminatum). Also noted are other bacterial, viral and parasitic diseases and, indeed, cancers of which Kaposi's sarcoma is the example, even though these are not manifested anorectally. New data on Kaposi's sarcoma, its' relationships with venereal disease and AIDS are presented. With these complex problems, the central role of male homosexuality and lowered cellular immunity widens considerably the professional scope of the proctologist.