This paper summarizes the recent findings of our laboratory on the mechanical properties of parallel fibered soft connective tissues. Using the improved experimental methodology developed in recent years, it is possible to overcome some of the past experimental difficulties and as a result, more reliable data on the stressstrain relationships for the digital flexor and extensor swine tendons and the medial collateral ligaments of the swine and dog were obtained. Furthermore, the experimental data was used in conjunction with a nonlinear viscoelastic theory to determine the time and history dependent properties of these tissues. A detailed example using the canine medial collateral ligament is reported to illustrate this combined approach.