More or less, a constant number of infectious type (skin smear positive for acid fast bacilli) of leprosy cases is being identified in Mumbai district for the past 5 years. More than 50-60%of them are migrated cases from other parts of India. The immigrants, whose identification is logistically difficult with existing mechanism, essentially maintain transmission of the disease. Most of these cases report voluntarily to general health services. Of course, finally land to specialized leprosy treatment canters.