Context Advance care planning (ACP) improves alignment between patient preferences for life-sustaining treatment and care received at end of life (EOL). Objectives To evaluate implementation of lay navigator-led ACP. Methods A convergent, parallel mixed-methods design was used to evaluate implementation of navigator-led ACP across 12 cancer centers. Data collection included 1) electronic navigation records, 2) navigator surveys (n = 45), 3) claims-based patient outcomes (n = 820), and 4) semistructured navigator interviews (n = 26). Outcomes of interest included 1) the number of ACP conversations completed, 2) navigator self-efficacy, 3) patient resource utilization, hospice use, and chemotherapy at EOL, and 4) navigator-perceived barriers and facilitators to ACP. Results From June 1, 2014 to December 31, 2015, 50 navigators completed Respecting Choices® First Steps ACP Facilitator training. Navigators approached 18% of patients (1319/8704); 481 completed; 472 in process; 366 declined. Navigators were more likely to approach African American patients than Caucasian patients (20% vs. 14%, P < 0.001). Significant increases in ACP self-efficacy were observed after training. The mean score for feeling prepared to conduct ACP conversations increased from 5.6/10 to 7.5/10 (P < 0.001). In comparison with patients declining ACP participation (n = 171), decedents in their final 30 days of life who engaged in ACP (n = 437) had fewer hospitalizations (46% vs. 56%, P = 0.02). Key facilitators of successful implementation included physician buy-in, patient readiness, and prior ACP experience; barriers included space limitations, identifying the “right” time to start conversations, and personal discomfort discussing EOL. Conclusion A navigator-led ACP program was feasible and may be associated with lower rates of resource utilization near EOL.