Major breakthroughs in the treatment of chemotherapy-induced emesis have come through the use of selective 5-HT3 receptor antagonists in combination with corticosteroids. This combination can be considered standard for most but not all commonly used chemotherapeutic agents. Delayed-onset emesis remains a problem, particularly for patients receiving high-dose cisplatin. There is debate over the value of using selective 5-HT3 receptor antagonists beyond the first 24 h. Clinical trials have not settled this uncertainty, although it seems likely that they add only modestly to the effect of corticosteroids. For both the acute and delayed phases, dopamine receptor antagonists may add to the effectiveness of antiemetic therapy. This article outlines a strategy for initial antiemetic therapy and the rationale for the recommendations.