This is a survey study for those with either upper limb loss or lower limb loss. We are interested in how you weigh the risks and benefits of prosthetic devices when you make decisions about their use or non-use. The survey can be taken on-line and takes from 30 to 45 minutes. You are asked to call (415-990-1012 or email [email protected] the researchers of your interest to hear about the study. We will explain the study to you, and if you are still interested, you will sign a consent. Then we will send you a link to the survey and you can take the survey. We send you a thank you when the survey is completed and $20 for your time