The Pet Partners Story

Early authors of the Pet Partners story

Michael and Bill McCulloch

Our story begins in the mid-1970s as the brainchild of a group of pioneers and visionaries:

  • Dr. Leo K. Bustad, a veterinarian
  • Two brothers, Dr. Michael J. McCulloch, a psychiatrist and Dr. William ‘Bill’ McCulloch
  • Veterinarians R.K. Anderson DVM, Stanley L. Diesch DVM, Joe Quigley DVM, and Alton Hopkins DVM

Long before animal-assisted interventions were documented to improve health, these professionals aligned through a shared observation. They saw that pets were having a positive impact on their human clients’ health and happiness. Each had observed this phenomenon in their own practices (and personal lives).

They theorized there was much more depth to what they were witnessing and recognized that anecdotal stories were not enough to capture the attention of the medical community. They concluded that scientific research was needed. A search of existing medical journals quickly revealed that little information was to be found, so they committed themselves to ensuring research would be completed to further explore the effects that animals have on people’s lives.

Pet Partners Founder who developed the term human-animal bond, Leo Bustad

Leo Bustad

With this aim in mind, the the Delta Foundation was formed in 1977 in Portland, Oregon with Michael J. McCulloch, MD as the President. In 1981, the organization’s name was changed to Delta Society, symbolizing the rapid expansion of a group of interested researchers and medical practitioners in both human and animal fields. At this time Leo K. Bustad, DVM, PhD became President. Bustad is widely credited with introducing the term “human-animal bond.”

During the early 1980s, Delta Society leaders paved the way in recognizing the importance of the human-animal bond. In 1981, co-founder, Bill McCulloch, DVM helped initiate the AVMA Human-Animal Bond Task Force to review the profession’s role in recognizing and promoting the human-animal bond. This AVMA Committee continues to this day. Delta Society leaders were also instrumental in helping with the passage of the Housing and Urban Rural Recovery Act of 1983. Their testimony in Washington DC and the subsequent passage of the Act by the federal government sent a strong public signal that it recognized the therapeutic value of pets in Americans’ lives.

In the years that followed, research findings emerged, with remarkable conclusions. Early findings included evidence that time spent with an animal reduces blood pressure, lower stress and anxiety levels. Studies also demonstrated that the human brain releases chemicals known as endorphins (that trigger positive feelings) when interacting with animals. Bolstered by this critical scientific research, members of Delta Society recognized it was time to put this knowledge to use in everyday applications.

Through the late 1980s and early 90s, Delta Society continued to strengthen its presence in this expanding field. New initiatives were developed to build on the organization’s research foundation. These programs focused on providing direct services at the local community level. Among these initiatives was the Pet Partners® program. Pet Partners® was the the first comprehensive, standardized training in animal-assisted activities and therapy for volunteers and health-care professionals.

In 2012, Delta Society formally changed its name to Pet Partners® in order to convey its mission clearly. Our Therapy Animal Program has now grown to over 15,000 teams across the US, making approximately three million visits each year.

Our history is rich with ground-breaking work, and we invite you to become part of the next chapter in the Pet Partners story!