Polyamine biosynthesis inhibition is being studied intensively as a new approach to cancer chemotherapy. In order to utilize appropriately compounds that deplete intracellular levels of polyamines, the effects of polyamines depletion on tumor and normal cell growth and the interaction of these inhibitors with chemotherapeutic agents must be understood. These topics are discussed briefly with respect to the general rationale for the treatment of brain tumors, and a number of potential advantages and disadvantages of the use of polyamine biosynthesis inhibitors in cancer chemotherapy protocols are discussed.