Recent cytogenetic studies have revealed that several types of benign and malignant human soft tissue tumors are characterized by highly specific chromosome abnormalities. In this article, we review the primary and secondary chromosome aberrations detected in lipoma, uterine leiomyoma, Ewing sarcoma, rhabdomyosarcoma, myxoid liposarcoma, synovial sarcoma, and clear cell sarcoma of tendons and aponeuroses. The primary aberrations are unique for the particular tumor type and therefore are of diagnostic value. Most recent molecular studies indicate that several sarcoma-specific translocations result in the gene fusion and creation of tumor-specific proteins that are novel DNA transcription factors.