Partner Engineering and Science, Inc. is pleased to be featured on the 2021 Engineering News-Record Top 500 Design Firms list for the ninth straight year. On the 2021 list, which reflects 2020 revenue, Partner was ranked #147 out of 500.
“Being recognized once again on ENR’s Top 500 list after a rollercoaster year is something we are all proud of,” said Joe Derhake, PE, CEO of Partner. “As engineers supporting the real estate industry, we focused much of 2020 facilitating the real estate community’s adaptation to the COVID paradigm. But perhaps more importantly, we were able to rescue a lot of good talent that found themselves casualties of the recession.”
Those strategies paid off. During 2020, Partner’s revenue held steady with 2019 levels while the firm increased its headcount by 8% to a new record size of over 1,000 employees. Among the hires are several well-regarded industry professionals like Bob Barone, Gary Cohn and Justin Lia who joined its Construction and Engineering teams. This stable of new professionals bolsters the firms engineering, environmental and energy solutions for the full real estate lifecycle.
As ENR reports, the engineering community experienced a median revenue decline of 4.4% with backlogs taking the biggest hit, and yet the revenue shortfalls were not as severe as some observers had predicted.
In 2021, Partner has benefitted from the infusion of new talent as well as a strong real estate market. Derhake notes “I’m optimistic that 2021 will be a successful year.”

July 02, 2026
Adrienne Perez, an Environmental Due Diligence Consultant, joins as Technical Director for Agency Services in Partner Engineering and Science's environmental service line.

June 23, 2026
For commercial real estate owners, developers, and investors, the program offers a more flexible and efficient path to address contamination, particularly at lower-priority sites enrolled in voluntary cleanup.

June 24, 2026
Amid evolving and often uncertain federal regulations, state environmental agencies have increasingly taken the lead in developing policies to address PFAS.




