Unidirectional graphite/epoxy was characterized at various strain rates ranging from quasi-static to over 500 s⁻¹. Properties were obtained by testing thin rings 10.16 cm (4 in.) in diameter, 2.54 cm (1 in.) wide, and 6 to 8 plies thick under internal pressure. Unidirectional 0, 90, and 10-deg off-axis rings were tested to obtain longitudinal, transverse, and in-plane shear properties. In the dynamic tests internal pressure was applied explosively through a liquid, and the pressure was measured with a calibrated steel ring. Strains in the calibration and specimen rings were recorded with a digital processing oscilloscope. The data were processed and the equation of motion solved numerically by a minicomputer attached to the oscilloscope. Results were obtained and plotted in the form of a dynamic stress-strain curve. Times to failure were as short as 30 μs. The 0-deg properties which are governed by the fibers do not vary much with strain rate with only a moderate increase in modulus. The 90-deg properties show a marked increase in modulus and strength with strain rate. In-plane shear properties follow a similar trend, although less pronounced than transverse properties. In all cases ultimate strains do not vary much with strain rate.