Propelled by remarkable advances in the understanding of the pathological characteristics of Alzheimer disease (AD), the prospects for the treatment of the clinical disorder have brightened considerably in the past decade. Primary treatment is aimed at the core elements of AD: memory and other cognitive loss at the symptomatic level and the pathological characteristics of molecular, cellular, and neural systems at the biological level. Behavioral features, such as depression, delusions, anxiety, disordered sleep, and agitation, are considered secondary manifestations of AD, although these features have a major impact on the quality of life, functional effectiveness, and caregiver burden. The focus of this review is on recent developments in the primary therapy for AD.