We describe a multiplex polymerase chain reaction (PCR) method suitable for the detection of all T-cell receptor (TCR) gamma-chain gene rearrangements in patients with lymphoproliferative diseases. 40 patients with various lymphoproliferative disorders and 40 healthy individuals were tested. Clonal TCR gamma rearrangements were identified in all patients with malignant disorders, and in one of 10 cases with established reactive lymphocytosis but not in normal controls. In all individuals testing positive, the patient's specific V and J segment involved in the rearrangement could be determined by simply splitting the multiplex primer mix. Our data show that the multiplex PCR technique enables rapid, simple and sensitive screening for clonal TCR gamma chain gene rearrangements.