In 1977, a small group of people concerned about animal welfare issues in Ozaukee County formed the Ozaukee Humane Project. Their main focus was to provide educational programs for the area schools. As this group increased in number and received some community recognition and support, the name was changed to the Ozaukee Humane Society. In 1982, an office was established in the Manchester Mall in Grafton. This office, staffed by volunteers, was a referral service with a lost and found hotline for stray animals. Membership in the organization continued to grow and over the next four years plans were developed to create an Ozaukee Humane facility. This plan became a reality in October 1988 when the shelter in Grafton opened its doors.

OHS is a not-for-profit organization and relies on generous and caring individuals to fund the services that OHS provides. Volunteers help maintain the operation and along with staff, provide compassionate care to nearly 2,000 animals each year. Comprehensive services are available to involve the community and find homes for abandoned animals.

In 2004, OHS merged with the Wisconsin Humane Society to expand the lifesaving opportunities available to animals in Ozaukee County. Shared administration functions ensure that community members can be even more confident that their resources will be used wisely to help animals in Ozaukee County. Because of their long and illustrious history of serving the Milwaukee community for 130 years, WHS is also known as the Milwaukee Humane Society.

The Ozaukee Humane Society offers a number of specialized services, including: