Remembering Gregory Castle
It is with profound sadness that we share the news that Best Friends co-founder and former CEO Gregory Castle passed away suddenly on Saturday, May 17, 2025, from natural causes.
Gregory was a brilliant, kind, and visionary leader who in his former role as Best Friends CEO brought direction and stability to the organization at a pivotal time of growth, helping to shape the organization’s pathway toward its mission. He was a pioneer in the no-kill movement and dedicated his life to saving animals.
Born in Cranbrook, England, in 1942, Gregory graduated from Cambridge University with a master's in philosophy and psychology, and he spent his last 41 years in Utah, where he quite literally helped build Best Friends from the ground up.
A self-proclaimed cat person, he lived with as many as 21 cats during the early days of Best Friends, when 17 million pets were still being killed in U.S. shelters. In recent years however, he shared his home with cats Ellie and Maggie and dogs, including his beloved German shepherds Shadow, Sunny, and Marley, whom he adopted from Los Angeles shelters. They became his loyal running buddies.
An avid runner, Gregory completed 17 marathons over a 20-year period, including three Boston Marathons, and at 73 became the oldest person to have ever completed the grueling seven-day, 170-mile Grand to Grand Ultra through Utah's backcountry.
Gregory was 83 years old. His legacy will live on through the large and dedicated national community of animal lovers working to save the lives of homeless pets. He will be deeply missed.
