An experimental model of acute compartment syndrome involving the anterolateral compartment of the hindlimb in dogs was used to compare three methods of measurement of intracompartmental pressure: the simple-needle technique, use of the slit catheter, and use of the side-ported needle. No statistical difference was found between the values obtained with the slit catheter and those obtained with the side-ported needle; the mean difference was 1.4 millimeters of mercury throughout the range of compartment pressures that were measured. The side-ported needle appeared to be as accurate as the slit catheter for the measurement of compartment pressures (p = 0.355, 1-beta = 0.9). The values obtained with use of the simple needle were consistently higher than those obtained with the other two methods (p < 0.001): an average of 18.3 millimeters of mercury higher than the values measured with the slit catheter and 19.3 millimeters of mercury higher than those measured with the side-ported needle. Clinically, the side-ported needle or the slit catheter can be used to obtain accurate measurements of compartment pressure. Use of the simple 18-gauge needle is not recommended for this purpose.