In Reply We appreciate the insightful comments from Dr Haffty and colleagues from the American Society for Radiation Oncology (ASTRO). Haffty et al suggest that active surveillance was not widely accepted during the study period from 2004 through 2007 with follow-up through 2009. Klotz1 published the landmark study in the first of many active surveillance results in 2005. Moreover, another landmark study was published in 2005 by Albertsen et al,2 which found the annual mortality rate from prostate cancer to remain stable after 15 years from diagnosis and no longer supported aggressive treatment for low-risk prostate cancer. Subsequent incorporation of active surveillance into the American Urological Association (AUA) guidelines for prostate cancer treatment and management occurred in 2007.3 Prior to this, knowledge of active surveillance for low-risk prostate cancer was becoming more accepted; however, we agree that dissemination even in recent years has remained slow. We applaud efforts from organizations such as the AUA, ASTRO, and the National Comprehensive Cancer Network (NCCN) who are actively making patients and clinicians aware of discussing active surveillance for low-risk disease. Further research discerning predictors for use of active surveillance is needed in order to limit overtreatment in this population.