More than 2% of the U.S. population in the age group 45 to 64 years uses an artificial leg or foot.  An estimated 20%-42% of lower extremity amputees show signs of skin breakdown.  The effects of residual limb ulceration go beyond physical skin irritation.  Ulcers can take weeks to treat and heal, resulting in loss of personal productivity and a documented negative effect on an amputee’s quality of life.  Amputees will discontinue the use of their prosthesis due to pain and discomfort and this will limit their level of mobility.  Preventing ulcers from forming on the residual limb is stated as a high priority in a survey of amputees.  We are developing sensors for the measurement of pressure and shear stress on the residual limb. The goal is to increase the understanding of skin irritation and breakdown on the residual limbs of amputees and to decrease the high incidence of residual limb ulcers and skin lesions.