Robot tool-center-point (TCP) positions are critical elements in industrial robot application programs. Their measurements and accuracies rely on the actual geometries and positions of components in a robot cell. Tiny changes of the components such as robots, end-effectors, fixtures, parts in the robot cells will cause inaccuracies of robot TCP positions used in existing robot programs. This paper introduces the method of performing robot cell calibrations to recover the accuracies of originally defined robot TCP positions. This is done by employing a precise external measuring system that is able to calibrate the robot, end-effector, and fixture in a robot cell with spatial measurements and mathematical calculations. Successful applications of this technology allow rapid deployments of industrial robot applications by accurately transferring or downloading production robot programs between two "identical" robot cells.