Home modification interventions have the potential to provide support to informal caregivers; however, the impact of these interventions on caregivers is understudied, and adequate assessments are lacking. This study describes the development and preliminary psychometric properties of a performance-based assessment that identifies environmental barriers to performance of daily caregiving activities. An existing assessment of person-environment fit was modified using key informant interviews and was administered to 31 informal caregivers. The In-Home Occupational Performance Evaluation for Providing Assistance demonstrated reliability across raters, good internal consistency for all subscales, and convergent validity with existing measures. This assessment has the potential to guide home modification interventions and measure the impact on informal caregiving in the home.