Objective: This article examines the psychometric properties of the Casey Foster Applicant Inventory-Worker Version (CFAI-W), a questionnaire designed to assess the potential of foster family care applicants to provide foster care. Method: Retrospective data were collected from 208 foster care workers who completed two copies of the CFAI-W, one for the best foster family and one for the worst foster family they had ever known. Results: The CFAI-W demonstrated excellent internal consistency reliability and evidence of predictive and discriminant validity. Conclusions: The CFAI-W can be used in combination with other methods to introduce standardization and accountability to the assessment of foster parent applicants. (Contains 1 figure and 11 tables.)