[open door animal sanctuary | no-kill animal shelter | serving st. lous county area & jefferson county area - open door a Open Door Animal Sanctuary, founded in 1975, is the largest no-kill shelter in the greater St. Louis area (based on numbers of animals cared for on a daily basis). Open Door’s Mission is to provide homeless cats and dogs with the highest quality of life and a second chance to find a forever family. We serve the community by taking in stray, abused, neglected and otherwise unwanted cats and dogs and placing them up for adoption. Each day we provide shelter, food, medical care and LOVE for more than 300 animals. Every animal that comes to us has a home and a second chance at life.]