Budmonster, there are many different kinds of SDs. Some alert to the onset of their human's medical condition, such as seizures or diabetic highs/lows. Some help a person with laundry, retrieving items off the floor or low places, or even helping the person get their wheelchair up an incline. Some guide blind/visually impaired people around obstacles, streets, stores, etc. Some alert to sounds for people who are deaf or hearing impaired. I just read a news article yesterday about a girl who just got a dog who sniffs out peanut traces (and keeps her away from them) because she is deathly allergic to even the tiniest traces of peanuts in soil, on people's hands, in a cabinet in the same room, etc.
My dog helps me walk by doing a series of mobility tasks, retrieves items I've dropped, retrieves items that are out of reach (when I'm in pain or need to reserve my energy so can't get up to get them), and several other helpful things that are associated with my particular disabilities. She loves her job!
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