In general, an <a href="https://en.wikipedia.org/wiki/assistance_dog" class="extiw" title="en:assistance dog">assistance dog</a>, known as a service dog in the United States, is a dog trained to aid or assist an individual with a <a href="https://en.wikipedia.org/wiki/disability" class="extiw" title="en:disability">disability</a>.
<a href="//commons.wikimedia.org/wiki/User:John_Robert_McPherson" title="User:John Robert McPherson">John Robert McPherson</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>