A family is presented in which 4 male siblings developed transitional cell carcinoma (TCC). Four upper tract tumours occurred in 3 and in the fourth the tumour was intravesical. Two of these patients also had colorectal adenocarcinoma. There were 2 other relatives in the pedigree with large bowel cancer. It is suggested that this is an example of Lynch Syndrome II, a hereditary non-polyposis colorectal cancer with extracolonic cancer sites. The implications regarding the screening, surveillance and detection of possible carrier status in healthy relatives is discussed.