Emerging evidence shows the benefits of honoring preferences in care for older adults. However, the mechanisms through which preference-based care affects individual well-being are poorly understood. The Preference-Based Model of Care integrates five key theories — Theory of Human Motivation, Self-Determination Theory, Competence-Press Model of person and environment fit, Living Systems Framework, and Broaden-and-Build theory of positive emotions — to deepen understanding of the way preference-based care may affect well-being. The Preference-Based Model of Care provides a framework to advance research and clinical practice in person-centered care.