A compression testing machine was used to transmit increasing loads at various strain rates across twelve canine and twelve human cadaver knees. The specimens were originally evaluated with both menisci intact and the same tests were repeated with one meniscus removed and then with both menisci removed. This investigation showed that the menisci perform a load-transmitting and energy-absorbing function in the knee joint. The stress acting across the joint increased significantly after meniscectomy. The intact meniscus was deformed during compressive loading rather than being passively pushed away, thus demonstrating the presence of hoop stresses within the meniscus.