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About Us

For nearly 60 years, CASCO has maintained its reputation for excellence because of its attention to client’s needs and wants. Our clients define our success as we focus on their input to design the buildings where their businesses grow and flourish. Our clients strive to impact their areas of expertise and we strive to provide the environment that encourages their success. Your needs, your goals provide the impetus that we approach each project with because your building reflects your creative enterprise. Our goal is to design the space where both you and your clients will share successful endeavors. Our talented staff recognizes that our job is to listen to you and in collaboration, implement your visions that optimize the environment that transcends into successful business opportunities.

CASCO + R|5 Lobby


Founded in 1958, CASCO  has a rich history of Engineering and Architecture services.  Our defining strength then and now is the commitment to quality and service provided by exceptional talent and dedicated account and project managers. CASCO’s core competencies provide nationwide leadership in design and engineering.

Today over 100 strong, CASCO’s team offers a high level of vertical integration as we grow into new and exciting markets. Our expanding civil department brings expertise in site work/land development, storm water and roadway design. The 2015 launch of our creative design team R|5 provides a holistic approach to design solutions in hospitality, restaurant, and specialty retail surroundings. Their award-winning work and collaboration is sought by some of the country’s top chefs and luxury retailers.

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CASCO + R|5 Leadership Team

Leadership Team

CASCO’s forward thinking team develops solutions in an ever-changing industry. We are advocates and advisers to our clients to fully address their unique needs, challenges, and success. In turn, our clients look to us as partners in their future.


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CASCO + R|5 History


CASCO evolved from a civil and structural engineering firm originally established by E. George Cassis, P.E. in Litchfield, Illinois in 1959.  Mr. Cassis was a Civil Engineer, earning his B.S. at the University of Missouri, his M.S. at Yale, and ultimately his Ph.D. at Yale and Columbia Universities. Mr. Cassis relocated his firm to Kirkwood, MO in 1962 and it became incorporated as Cassis Associates, Inc. in June of 1963.  Around 1965, in a joint venture with William en Tao and Associates, Cassis Associates built a new office building at 2357 59th Street in south St. Louis.  The new facility was shared by both firms.


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Careers at CASCO + R|5

Careers at CASCO

We’re seeking the brightest and most talented minds to be part of our emerging culture.​ The successful candidate will emphasize client service and utilize their aptitude to create progressive design...


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