From the website:
We believe that animals are entitled to kind and respectful treatment at the hands of humans, and must be protected under the law.
The American Society for the Prevention of Cruelty to Animals (ASPCA) was the first humane society to be established in North America and is, today, one of the largest in the world. Our organization was founded by Henry Bergh in 1866 on the belief that animals are entitled to kind and respectful treatment at the hands of humans, and must be protected under the law. Headquartered in New York City, the ASPCA maintains a strong local presence, and with programs that extend our anti-cruelty mission across the country, we are recognized as a national animal welfare organization. We are a privately funded 501(c)(3) not-for-profit corporation, and proud to boast more than 1 million supporters across the country.
Of course there are many organizations in which to adopt, including families who foster pets for adoption. Just be sure to do your research, ask friends, make smart choices. But pets are an amazing thing.