I have volunteered at several shelters over the years. It's hard seeing the animals in the shelter and not being able to give every one of them homes. It is also hard knowing that many are killed due to insufficient homes. It is actually very heartbreaking to know that these animals are there unwanted usually, by no fault of their own. However, that said, it is good to be able to help them in any way you can. I think volunteering at a shelter is a great way to lend a hand and help others; it is also a very helpful experience if you plan on working in any animal care field.