The installation of a cyclotron (Cyclotron Corp. CS‐15) in an existing building without disruption of other operations was accomplished with relatively little difficulty using overdesigned shielding (6 feet of ordinary concrete). Background measurements on a whole‐body counter 50 feet away on the same floor were increased only 10% summing over the whole spectrum. Available space in the vault is 18 × 13 feet, permitting convenient operation of a 3‐port target facility oriented vertically. The operating responsibility has been entirely in the hands of personnel without previous experience, with engineering and physics back‐up when needed for repairs, maintenance and improvement of the machine. The targetry has been handled almost entirely by the operating staff. During the first three years of operation, down time has been insignificant (∼10%), almost equally divided between component failure and operator error. Applications have been in the production of radionuclides for experimental and clinical use. 66G...