Advances in the field of oncology have led to the development of many antineoplastic agents for the treatment of cancer. Combination with other agents and modalities, along with dose intensification, has resulted in more toxicities, often requiring careful management and monitoring in the critical care setting. Critical care nurses must meet this challenge by expanding their knowledge of antineoplastic therapy in order to skillfully care for these patients. The six major categories of antineoplastics, mechanism of action, indications for use, common route of administration, and major side effects are discussed.