This paper establishes a standard method for measuring human tremor. The electronic instrument described is an application of this method. It solves the need for an effective and simple tremor-measuring instrument fit for wide distribution. This instrument consists of a piezoelectric accelerometer connected to an electronic circuit and to an LCD display. The signal is also analysed by a computer after accelerometer analogic/digital conversion in order to test the method. The tremor of 1079 healthy subjects was studied. Spectral analysis showed frequency peaks between 5.85 and 8.80 Hz. Chronic cigarette-smoking and coffee drinking did not modify the tremor as compared with controls. Relaxation session decreased tremor significantly in healthy subjects (P less than 0.01). This new tremor-measuring method opens new horizons in the understanding of physiological and pathological tremor, stress, anxiety and in the means to avoid or compensate them.