Olanzapine is a novel antipsychotic agent displaying a unique and pleotrophic pharmacology, which distinguishes it from other existing treatments. Clinical investigations employing olanzapine have demonstrated a number of potential therapeutic advantages in reference not only to placebo but also to contemporary drug standards in the management of psychosis. This paper reviews data on the pharmacokinetics, efficacy and safety of olanzapine, its benefits for quality of life, and economic aspects to assist clinicians in determining where they can usefully employ it.