With 100+ years experience managing complex outsourced services for some of the largest companies and government groups, Day & Zimmermann delivers the innovative solutions our customers need to overcome their toughest challenges.

We have built our reputation across a diverse portfolio of businesses and have been continuously recognized for our achievements, particularly in the area of safety. Some of our most recent achievements and recognition include:

• #1 Operations & Maintenance Contractor in Power according to Engineering News-Record (September, 2012)
• #15 among Top Chemical Plants Contractors according to Engineering News-Record (September, 2012)
• #3 among Top Mid-Market RPO (Recruitment Process Outsourcing) Providers (Yoh) according to HRO Today (September, 2012)
• #140 among Top Global Contractors according to Engineering News-Record (August, 2012)
• #61 among Top Green Design Firms according to Engineering News-Record (July, 2012)
• #5 among Top Design Firms in Chemical Plants according to Engineering News-Record (July, 2012)
• #9 among Top Design Firms in Industrial Process according to Engineering News-Record (July, 2012)
• #116 among Top Design Firms according to Engineering News-Record (July, 2012)
• #99 among the Top 100 Global Defense Contractors according to Defense News (June, 2012)
• #34 among Top Contractors according to Engineering News-Record (May, 2012)
• #4 among Top Power Contractors according to Engineering News-Record (May, 2012)
• #186 among Largest Private Companies according to Forbes (November, 2011)
• #1 Operations & Maintenance Contractor in Power according to Engineering News-Record (September, 2011)
• #93 among the Top 100 Global Defense Contractors according to Defense News (August, 2011)
• #2 among Top RPO (Recruitment Process Outsourcing) Providers (Yoh) in projects/on demand category according to HRO Today (August, 2011) 
• #5 among Top Managed Services Programs (Yoh) according to HRO Today (June, 2011)
• The Association of Union Constructors (TAUC) Thomas J. Reynolds Award for excellence in construction safety (May, 2011)
• #29 among the Largest U.S. Staffing Firms (Yoh) according to Staffing Industry Analysts (May, 2011)
• #5 among Top Design Firms in Chemical Plants according to Engineering News-Record (May, 2011)
• #12 among Top Design Firms in Industrial Process according to Engineering News-Record (May, 2011)
• #20 among Top Design Firms in Government according to Engineering News-Record (May, 2011)
• #35 among Top Contractors according to Engineering News-Record (May, 2011)
• #5 among Top Power Contractors according to Engineering News-Record (May, 2011)
• 2010 Thomas J. Reynolds Award for construction safety and health from The Association of Union Constructors (March, 2011)
• #206 among Largest Private Companies according to Forbes (November, 2010)
• 2010 Occupational Award winner from the National Safety Council (October, 2010)
• #1 among Top Contractors in Power Operations and Maintenance according to Engineering News-Record (September, 2010)
• #109 among Top Technology Innovators as ranked on the InformationWeek 500 (September, 2010)
• Yoh recognized with three Staffing VOICE Awards from the American Staffing Association (August, 2010) 
• #26 among the Largest U.S. Staffing Firms (Yoh) according to Staffing Industry Analysts (July, 2010)
• #10 among Largest U.S. Clinical/Scientific Staffing Firms (Yoh) according to Staffing Industry Analysts (July, 2010)
• #13 among Largest U.S. Engineering Staffing Firms (Yoh) according to Staffing Industry Analysts (July, 2010)
• #25 among Largest U.S. IT Staffing Firms (Yoh) according to Staffing Industry Analysts (July, 2010)
• #87 among the Top 100 Global Defense Contractors according to Defense News (July, 2010)
• #54 among Top Green Design Firms according to Engineering News-Record (July, 2010)
• #8 among Top Design Firms in Chemical Plants according to Engineering News-Record (July, 2010)
• #11 among Top Design Firms in Industrial Process according to Engineering News-Record (July, 2010)
• #20 among Top Design Firms in Government according to Engineering News-Record (July, 2010)
• #8 among Top Power Contractors according to Engineering News-Record (May, 2010)
• #44 among Top Contractors according to Engineering News-Record (May, 2010)
• #11 among Top Guard Firms according to Security Magazine (February, 2010)
• #53 among Largest Private Family-Owned Companies according to Family Business Magazine (Winter, 2009)