The purpose of this study was to examine the reliability of using an isovelocity dynamometer for the testing of four movements of the shoulder and shoulder girdle in participants having a spinal cord injury. Ten people with quadriplegia and ten people with paraplegia participated in the study. The movements being tested included shoulder girdle (scapular) elevation and depression, and shoulder (glenohumeral joint) flexion and adduction. Scapular movements were tested using a standardised reciprocal protocol at an angular velocity of 30/s, while glenohumeral movements were tested using a standardised protocol at an angular velocity of 60/s. Testing was conducted on two days separated by no less than 72 hours, but no more than one week. Data analysis showed high reliability for all tested movements with intraclass correlation values greater than 0.9, and r2 values greater than 0.76. The protocol and the isovelocity dynamometer used is a reliable means to assess force generated in these movements by participants with spinal cord injuries.