© 2020, Springer Science+Business Media, LLC, part of Springer Nature. Nausea and vomiting is a common clinical issue in the advanced cancer patient. The etiology may be related to treatment (chemotherapy, radiation, surgery) or non-treatment clinical issues related to the advanced cancer. A very detailed initial assessment of nausea/vomiting is indicated including frequency, duration, intensity, associated activities, and the presence of anorexia or cachexia and is necessary in order to determine a specific etiology which may allow a potentially specific successful intervention. Various international antiemetic guidelines have been developed for the successful prevention of chemotherapy- and radiotherapy-induced nausea and emesis but the treatment of post-chemotherapy nausea/vomiting and of radiation-induced nausea/vomiting has been less successful. Chronic nausea/vomiting in the advanced cancer patient unrelated to treatment remains a significant clinical problem with few successful treatments and interventions. NCCN and ASCO palliative care guidelines provide various treatment suggestions but these are based on empiric evidence with very few clinical trials available to provide demonstrated effective treatments. Recent randomized clinical trials have demonstrated that olanzapine may be an effective agent for the prevention and treatment of chemotherapy-induced nausea and emesis as well as treatment of chronic nausea and vomiting unrelated to treatment.