Company Profile

Day & Zimmermann is a century-old, family-owned company specializing in construction & engineering, operations & maintenance, staffing, security and defense for leading corporations and governments around the world.

Our vision is to accelerate the next generation of innovation.

Chairman & CEOHarold L. Yoh III
Annual Revenue: $2.5 Billion
Global Workforce: 43,000
Headquarters: 1500 Spring Garden Street, Philadelphia, PA 19130
Media Contact: Suzanne Watts

Our customer promise: We do what we say.®

  • Global Workforce


  • Founded in 1901


  • $2.5 Billion Annual Revenue


  • 150+ Worldwide Locations


  • Footprint at 60% of the U.S. nuclear fleet


  • Ranked in Top 100 Defense Companies


  • #1 Ranked Operations & Maintenance Contractor for 10 consecutive years (ENR)


  • Ranked #179 on the Forbes America's Largest Private Companies List


  • Yoh Named to HRO Today's RPO Baker's Dozen list


Our People
are Our Future

In a constantly changing world it’s not businesses, governments and institutions that will build the future. It’s the people behind them. For more than a century Day & Zimmermann has hired, placed and trained the people that helped bring big ideas to life.

Diversity & Inclusion at Day & Zimmermann

Our Diversity Vision

To be a company that embraces diversity, is inclusive, and thrives on learning so that our employees feel respected and invited to contribute to the success of our company, clients, suppliers and communities.

Learn More

We are Many, Diverse Voices of Betterment

Our People

The best way to learn about life at Day & Zimmermann is to hear from the people who are living it. Meet the people behind our success.

Learn More About Life at D&Z

“I am excited to be part of an amazing organization and work with colleagues who share the same values as I have.”