Traditional measurement approaches in health care focus on group data, virtually ignoring the individual client. To demonstrate the distinct value of occupational therapy, we need a measurement model that focuses on the person and generates outputs to inform daily practice. Traditional methods of establishing norms and predictive validity do not inform the development of interventions and goal setting. In this Eleanor Clarke Slagle Lecture, I use a person-centered measurement model that focuses on the person, versus the instrument, to demonstrate how person-centered measurement can be immediately used to identify the just-right challenge for the client. Person-centered measurement can be both the basis for designing interventions specific to the client and the foundation for setting empirically appropriate short-term and long-term goals. Occupational therapy practitioners can lead health care by immediately applying person-centered measurement to address the needs of individual clients and, moreover, to reveal the distinct value of occupational therapy.