John Mulvihill, MS, longtime technical manager of the Radiation Resources Facility, announced his retirement last month. John is a skilled physicist who managed the facility for over 30 years, during which time he demonstrated complete dedication to making it work for all users. Past facility directors praised John for this ability to navigate the complicated systems and requirements related to the facility's activities and ensure user research was conducted in a safe environment. All irradiator users greatly appreciated John's expert input and especially benefited from John's generous willingness to make himself available to researchers whenever needed to facilitate their research efforts. John was a special resource because he cheerfully was there to help anyone with their work under all circumstances. His willingness to be available nights and weekends to accommodate demanding experimental protocols was a unique and much-appreciated contribution. Former Radiation Resources director Nancy Oleinick, PhD, summarized it best, "The University and the Cancer Center were fortunate to have hired and retained John. I wish him well in his retirement."