In South Korea, the Community Youth Safety-Net (CYS-Net) provides a comprehensive network for preventing and combating issues of at-risk adolescents through counseling. To measure the CYS-Net counseling outcomes reliably, the Korean Youth Counseling Outcome Scale (KYCOS) was developed. In this study, we reviewed and summarized related research conducted in the last few years, from the development of the KYCOS in 2007 to its implementation within the CYS-Net system. Specifically, this study first investigated other outcome questionnaires that had similar developmental contexts and needs. Then, the characteristics and technical adequacy of the KYCOS were described. The KYCOS was found to fit the Korean context effectively and to be reliable and valid. The KYCOS allows the objective presentation of youth counseling outcomes and increases the level of accountability among counseling professionals. The resulting quality improvement of youth counseling services will ultimately promote greater utilization of services and facilitate related research.