The Day & Zimmermann Group, Inc.
Day & Zimmermann offers services as distinct as day and night. Its family of companies provides engineering and construction, design, plant maintenance, security, staffing, munitions decommissioning, validation, and asset management services worldwide. A top global contractor, Day & Zimmermann provides operations, contract support, and maintenance services to US and foreign governments, as well as commercial customers. Its Day & Zimmermann NPS unit maintains half of the US's nuclear plants. Staffing subsidiary Yoh Services specializes in filling IT, engineering, and health care positions. Founded in 1901, Day & Zimmermann is owned and managed by the Yoh family, which has headed the firm for three generations.