Objective: To develop and test face and content validity, and user interface design of a rehabilitative care patient experience measure.; Design: Mixed methods, cross-sectional validation study that included subject matter expert input. Cognitive interviewing tested user interface and design.; Setting: Outpatient rehabilitative care settings.; Participants: Subject matter experts (n=3), health care providers (n=137), and patients and caregivers (n=5) contributed to the question development. Convenience and snowball sampling were used to recruit rehabilitative care patients postdischarge (n=9) for cognitive interviews to optimize survey design and user interface (N=154).; Interventions: Not applicable.; Main Outcome Measure: This novel survey instrument measures 6 concepts previously identified as key to outpatient rehabilitative care patients' experience: ecosystem issues, client and informal caregiver engagement, patient and health care provider relations, pain and functional status, group and individual identity, and open-ended feedback.; Results: 502 survey questions from psychometrically tested instruments, secondary data from a related ethnographic study, and consultations with health care providers, patients, caregivers, and subject matter experts, were analyzed to create a 10-item questionnaire representing 6 key constructs that influence patient experience quality. Cognitive interviewing with 9 patients (3 rounds of 3 participants each), produced 3 progressively edited versions of the survey instrument. A final version required no further modifications.; Discussion: Rehabilitative care clients have characteristics that differentiate their experience from that of other sectors and patient groups, warranting a distinct experience measure. The survey instrument includes a parsimonious set of questions that address strategic issues in the ongoing improvement of care delivery and the patient experience in the rehabilitative care sector.; Conclusion: The rehabilitative care patient experience survey instrument developed has an acceptable user interface, and content and face validity. Psychometric testing of the survey instrument is reported elsewhere.