Jim Hartmann will begin work with the county in April. Hartmann is currently the manager of Seminole County, Florida and has previously served as manager of Alexandria, Va.
Hartmann will be responsible for the administration of all county departments and agencies under the guidance of the Board of Commissioners.
"Jim Hartmann has both the practical experience and long term perspective that we were looking for in a manager," Wake County Board of Commissioners chair Phil Matthews said in a statement. "Every member of the Board felt he was the best candidate and we look forward to working with him and to continue Wake County's traditions of excellence."
In November, Cooke retired after 13 years as manager. He oversaw a $980 million budget, 3,800 employees, and all county services.