http://www.hsus.org
2. PETA
http://www.peta-online.org
3. Progressive Animal Welfare Society
http://www.paws.org
4. ASPCA
http://www.aspca.org
5. American Humane Association
http://www.americanhumane.org
6. Hugs For Homeless Animals
http://www.h4ha.org
7. Animal Protection Institute
http://www.api4animals.org
8. Performing Animal Welfare Society
http://www.pawsweb.org
9. Defenders of Wildlife
http://www.defenders.org
10. Animal Liberation
http://www.animal-liberation.net