In 1996, ACA's Standards Committee developed a vision of new health care standards for correctional facilities that would measure performance and prescribe conditions to be achieved and maintained. This led to the development of performance-based standards. ACA conducted numerous activities in 1997 and 1998 that involved practitioners and experts in converting standards and accreditation into a "continuous quality improvement process." After successful field testing, the Performance-Based Standards for Adult Community Residential Services were adopted and published in August 2000. Since then, the ACA has expanded the performance-based approach to its standards for correctional health care in adult correctional institutions, adult local detention facilities, correctional industries, therapeutic communities, and health care in juvenile facilities. As conditions in correctional health care change and as practitioners learn from experience, practices and outcome measures should evolve to reflect the growing body of medical knowledge and experience. An example of such a change is in the outcome measures of the forthcoming revised Performance-Based Standards for Correctional Health Care in Adult Correctional Institutions. New outcome measures for Performance Standard 1A reflect a relatively recent and growing concern about methicillin-resistance staphylococcus aureus (MRSA) among correctional practitioners in the field. The ACA will also soon release the new Performance-Based Standards for Correctional Health Care in Juvenile Facilities. These new standards for adult and juvenile health care were field tested successfully with volunteer agencies before being approved. ACA will continue to expand the "outcome measure" approach to health care standards and encourage feedback from those in the field who use them.