Alzheimer's disease (AD) is a complex progressive brain degenerative disorder that has effects on multiple cerebral systems. In addition to cognitive and functional decline, diverse behavioral changes manifest with increasing severity over time, presenting significant management challenges for caregivers and health care professionals. Almost all patients with AD are affected by neuropsychiatric symptoms at some point during their illness; in some cases, symptoms occur prior to diagnosis of the dementia syndrome. Further, behavioral factors have been identified, which may have their origins in particular neurobiological processes, and respond to particular management strategies. Improved clarification of causes, triggers, and presentation of neuropsychiatric symptoms will guide both research and clinical decision-making. Measurement of neuropsychiatric symptoms in AD is most commonly by means of the Neuropsychiatric Inventory; its utility and future development are discussed, as are the limitations and difficulties encountered when quantifying behavioral responses in clinical trials. Evidence from clinical trials of both non-pharmacological and pharmacological treatments, and from neurobiological studies, provides a range of management options that can be tailored to individual needs. We suggest that non-pharmacological interventions (including psychosocial/psychological counseling, interpersonal management and environmental management) should be attempted first, followed by the least harmful medication for the shortest time possible. Pharmacological treatment options, such as antipsychotics, antidepressants, anticonvulsants, cholinesterase inhibitors and memantine, need careful consideration of the benefits and limitations of each drug class.