Recovery from serious mental illness refers to the attainment of a meaningful, productive, and satisfying life, regardless of the presence or absence of reoccurring symptoms. A lack of psychometrically sound instruments has thwarted attempts to measure recovery. With the goal of addressing this need, we administered the Recovery Assessment Scale (RAS) to 92 people with serious mental illness attending a Clubhouse program. Clubhouses are community-based psychosocial rehabilitation programs for people living with mental illness. Rasch analysis enabled close examination of the RAS’s internal validity and reliability. Through iterative analyses, we made enhancements to the instrument where possible. The preponderance of evidence suggests that the modified RAS forms a unidimensional construct; however, the instrument remains far from a gold standard. Occupational therapy is well suited to take leadership in further development of this instrument.