Dr. Hallman did his undergraduate work at the University of Wyoming. He received his Doctor Of Veterinary Medicine degree from Kansas State University in 1985. Dr. Hallman opened Star Valley Veterinary Clinic in May 1985. He has two children, Rand and Sage, and resides in Star Valley.

Dr. Hallman has been a consulting veterinarian for the Payson Humane Society, the Payson Rodeo, the Payson Zoo, the Payson Natural Resources Committee, and the Arizona Game and Fish Department. He donates his time working on wildlife projects throughout Arizona and other states. Sled dog medicine is a passion, and has been vetting sled dog races in Alaska and Canada since 1994, including the Yukon Quest 1000 Mile sled dog race and the Copper Basin 300 sled dog race. He served as the Yukon Quest Head Veterinarian in 1996 and 1997.

Dr. Hallman’s personal interests include spending time with his children, hiking, traveling, photography, and volunteer work.