Gene Mueller has been appointed manager of the Regional Animal Services of King County. Mueller is the administrator of Chicago’s largest critical-care veterinary hospital. He will assume his new duties June 4.

Mueller also serves as president of the Anti-Cruelty Society of Chicago, where he directs fundraising and managed a team of more than 100 employees and 400 volunteers.

Mueller replaces interim manager Glynis Frederiksen, who will return to her role as operations manager for the King County Pet Adoption Center in Kent.