Context. Advance care planning (ACP) is essential to elicit goals, values, and preferences of care in older adults with serious illness and on trajectories of frailty. An exploration of ACP uptake in older adults may identify barriers and facilitators. Objective. To conduct an integrative review of research on the uptake of ACP in older adults and create a conceptual model of the findings. Methods. Using Whittemore and Knafl's methodology, we systematically searched four electronic databases of ACP literature in older adults from 1996 through December 2019. Critical appraisal tools were used to assess study quality, and articles were categorized according to level of evidence. Statistical and thematic analysis was then undertaken. Results. Among 1081 studies, 78 met inclusion criteria. Statistical analysis evaluated ACP and variables within the domains of demographics, psychosocial, disability and functioning, and miscellaneous. Thematic analysis identified a central category of enhanced communication, followed by categories of 1) provider role and preparation; 2) patient/family relationship patterns; 3) standardized processes and structured approaches; 4) contextual influences; and 5) missed opportunities. A conceptual model depicted categories and relationships. Conclusions. Enhanced communication and ACP facilitators improve uptake of ACP. Clinicians should be cognizant of these factors. This review provides a guide for clinicians who are considering implementation strategies to facilitate ACP in real-world settings.