An increasing number of ambulatory surgery centers are undergoing accreditation to improve their level of care, gain more clout with payers, and increase credibility with physicians and patients. But as all who've attempted accreditation know, the process is costly and time-consuming, and even though few facilities fail completely, most obtain only partial compliance, requiring them to be re-surveyed in six months to a year. There are some facilities, however, that do get everything right the first time and achieve the elusive three-year status.