The two-phase composite correction program (CCP) can help water treatment plants comply with the Surface Water Treatment Rule by optimizing plant performance without making major capital expenditures. The first phase, the comprehensive performance evaluation (CPE), is a thorough analysis that identifies performance-limiting factors. The second phase, comprehensive technical assistance (CTA), is implemented if the CPE indicates performance can be improved. This article describes a program in which a CCP was implemented at 36 small and medium-sized utilities; only 2 were operating optimally, and several were considered threats to public health. Insufficient resources did not significantly limit performance of small water plants; instead, the primary problems were operational. Decreasing flows and increasing operating time were judged to be a practical alternative for plants operating less than 24 hours a day. In addition, exceeding a design standard to optimize multiple-barrier protection was found justifiable if the integrity of the overall process is maintained. Establishing adequate rate structures and motivating workers to pursue high-quality water as a treatment objective can overcome perceived resource barriers. After CTAs at four plants, finished-water turbidity requirements were achieved at a capital cost of less than $10,000 per plant. To achieve the maximum benefit, the CCP should be integrated with the existing state drinking water program. Includes 11 references, tables, figures.