Purpose: This study evaluated the psychometric properties of the Dyadic Relationship Scale (DRS), which measures negative and positive dyadic interactions from the perspective of both the patient and the family caregiver. An important aspect of evaluating the DRS was that it be statistically sound and meaningful for both members of the dyad. Design and Methods: The study used a cross-sectional design. Survey packages were mailed to home health care patients and their family caregivers. The unit of analysis was the dyad, and exploratory and confirmatory factor analyses were conducted. We examined the reliability, discriminant, and concurrent validities of the instrument. Results: The data supported a two-factor DRS that included negative dyadic strain (patient α =.84; caregiver α =.89) and positive dyadic interaction (patient α =.86; caregiver α =.85). The analysis supported the DRS's construct, discriminant, and concurrent validity, as well as its reliability for both patients and family caregivers. Implications: Using the DRS to measure the impact of family care on positive and negative interactions inclusive of patients and caregivers can assist in identifying areas of difficulty and guide interventions to improve outcomes for both members of the dyad.