Angel On A Leash began as a charitable activity of the Westminster Kennel Club in 2004, creating and administering a therapy dog program at the NewYork-Presbyterian Morgan Stanley Children's Hospital in the city.

Ronald McDonald House New York came next. Dogs had never been allowed in the House before Angel On A Leash created a therapy dog program in this home-away-from-home for pediatric oncology patients and their families. Providence Medical Center in Portland (Oregon), St. Jude Children's Research Hospital in Memphis and Hackensack University Medical Center in New Jersey soon became affiliated with Angel as well.

In 2007, Angel On A Leash became an independent 501(c)(3) charity and continued to expand across the country.

Today, Angel administers the therapy dog program at Memorial Sloan Kettering Cancer Center in New York, the Fisher House at the Michael DeBakey VA Medical Center in Houston, Children's Hospital of Wisconsin, and Ronald McDonald Houses in Memphis (at St. Jude) and Milwaukee (at CHW). Programs are also being planned for Shriners Hospitals for Children.

Angel also has agreements with four other partners: Mid South Therapy Dogs (MSTD) of Memphis, Intermountain Therapy Animals of Salt Lake City, Animal Medical Center of New York City, and the Pediatric Oncology Experimental Therapeutics Investigators' Consortium (POETIC). MSTD sends teams to approximately 40 facilities in the Greater Memphis area. ITA has developed a successful and widely-implemented animal assisted therapy program called Reading Education Assistance Dogs (R.E.A.D.). Animal Medical Center is a national leader in medical care for companion animals, and also world renowned for its outstanding teaching and research in the field of veterinary medicine. POETIC is composed of ten large academic medical centers in North America with emphasis on comprehensive cancer care and research.

Angel On A Leash has been very involved in projects around the country, but especially in its home base of New York City. Overseeing and recruiting for training classes and workshops, participating with booths at public events, support of local charities, and much more give Angel great visibility and credibility in pursuing its mission, in New York and elsewhere.