Abstract: An improved range of motion measuring and displaying device is disclosed herein which includes a modular housing containing a micro-computer and associated circuitry as well as input controls, display and printout facilities, input and output cord connections and a software receiving area which is provided so as to detachably connect to the modular housing diverse programs enabling diverse modes of operation of the invention. One of the cord connections is provided for attachment thereto of the cord of an electronic goniometer which has been designed specifically to interface with the modular housing. The electronic goniometer is of the variable resistance type and outputs voltages interpretable by the micro-computer which voltages are indicative of a rotation of the electronic goniometer with respect to an original vertical position.