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Sine Qua Non | Absolutely Essential

Services
Our Work
About SQN Associates
- Culture, Mission, and Values
- The SQN Team
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Services
Our Work
About SQN Associates
- Culture, Mission, and Values
- The SQN Team
Careers

TRANSPORTATION

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Our Work

ISTHA I-88 & Systemwide Construction Management Services

Learn More about ISTHA I-88 & Systemwide Construction Management Services

60D77 Final Product Ramp D 9

IDOT District One Palatine Road at Des Plaines River Frontage Road

Learn More about IDOT District One Palatine Road at Des Plaines River Frontage Road

CDOT Irving Park Bridge over North Branch of the Chicago River

Learn More about CDOT Irving Park Bridge over North Branch of the Chicago River

Project 1045 20210910 9

ISTHA Reagan Memorial Road Reconstruction (York Road to I-290)

Learn More about ISTHA Reagan Memorial Road Reconstruction (York Road to I-290)

20190312 M.Khan 1029 ISTHA 159th Street Bridge Casson Concrete Pour

ISTHA Tri-State Tollway, 159th Street Bridge Reconstruction

Learn More about ISTHA Tri-State Tollway, 159th Street Bridge Reconstruction

CDOT Smart Lighting

Learn More about CDOT Smart Lighting

SQN is certified as a Disadvantaged Business Enterprise (DBE) in GA/IL/IN/MA/UT/WI, Minority Business Enterprise (MBE), Women’s Business Enterprise (WBE), and Women-Owned Small Business (WOSB).

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134 North LaSalle Street, Suite 700, Chicago, IL 60602

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