CATIE-AD was a multicenter effectiveness trial of atypical antipsychotics in patients with agitation and psychosis associated with AD who resided in the community. The study enrolled 421 participants. In this paper we present and discuss baseline characteristics of participants (demographics, cognitive, behavioral, and functional assessments), caregivers (demographics and caregiver burden) and settings at randomization. Those enrolled suffered from a wide range of cognitive impairment, were medically complex and experienced acute psychopathology requiring intervention with atypical antipsychotics. Family members providing the equivalent of institutional care experienced significant depression and caregiver burden. With the increasing prevalence of AD, clinicians and health care planners should look into future needs of those AD sufferers who are residing in community.