A technique has been developed to determine the response of space frames to dynamic forcing. The method is based on the normal mode approach. Essentially, each structural component is considered individually and then the system is coupled together. This procedure gives rise to a series of independent second-order differential equations, expressed in terms of the normal coordinates of the composite structure. It also represents the structure as a continuous mathematical model and allows the application of distributed forces which are allowed in turn to vary arbitrarily with time.