The authors report the results of a preliminary study of muscular tension during handwriting in patients suffering from rheumatoid arthritis. 45 subjects were used and these were divided into 3 groups of 15 each as follows: (1) a group of "normal" control subjects, (2) a group of patients suffering from other disorders. The graphodyn was used for recording writing speed and pressure. Variations in frequency, amplitude, and wave-form of the tracings were markedly more prominent for the 2 groups of patients than for the control group of subjects. It is concluded "that a dysfunction of muscular performance does exist, not only in patients with rheumatoid arthritis, but also in patients with other diseases, such as hypertension. This dysfunction appears essentially to be a disturbance in the synergic use of the muscles, interfering with the delicate tension and release involved in the exptl. task of handwriting.".