Cytogenetic and related changes in human cancer constitute part of a constantly developing and enlarging continuum of known genetic alterations associated with cancer development and biology. The cytogenetic component of this continuum has fulfilled much of its pioneering role and now constitutes a small but dynamic segment of the vast literature on cancer genetics, in which it has played an important if not initiating role. The goals of this article are (a) to address historical and methodological aspects of cancer cytogenetics; (b) to present information on diagnostic translocations in leukemias, lymphomas, bone and soft tissue tumors, and carcinomas; (c) to connect some of these chromosomal aberrations with their molecular equivalents; and (d) to describe anomalies in some solid tumors indicative of the complexity of the genomic alterations in cancer. We also look at a few of the more recent genomic developments in cancer and offer an opinion as to what all these findings add up to.