Rotational depth profiling (RDP), also known as Zalar rotation [A. Zalar, Thin Film Solids 124, 223 (1985)], has been demonstrated by several groups [N. Veisfeld and J. Geller, J. Vac. Sci. Technol. A 6, 2077 (1988); E. Cirlin, J. Vajo, R. Doty, and T. Hasenberg, ibid. 9, 1395 (1991); E. Cirlin, Y. Cheng, P. Ireland, and B. Clemens, Surf. Interface Anal. 15, 337 (1990)] to eliminate the loss of depth resolution in multilayered materials by preventing ion sputter induced roughening. It is thought that the constantly changing angular orientation between the ion beam and the microcrystalline structure of the specimen evens out small differences in sputtering rates due to preferred orientation effects. The mechanical requirements for RDP are simple. The specimen is ion sputtered while it is rotating with the electron beam placed on the rotation axis. Published works to date involving RDP have been accomplished by placing the area to be profiled on the rotation axis. In practice, the runout or wobble of the rotation axis and the size of the electron beam determines what area is actually analyzed. It is very difficult to analyze areas less than (100 mum)2 [J. D. Geller and N. Veisfeld, Surf. Interface Anal. 14, 95 (1989)] without manually repositioning the specimen after each rotation and sputtering cycle. By automating the X, Y, and rotation manipulator axes, randomly selected areas to approximately 10 mum in size can be depth profiled without regard to the location of the rotation axis and without the need for operator repositioning of the specimen. Mathematical derivations of the rotation calculations, actual performance of the computer controlled manipulator, and practical applications are discussed.