o Jack Sbertoli founded John Martin Companies with the expectations of bringing senior leadership to the project management decision table on a daily basis. Mr. Sbertoli has worked in nearly every market sector in the commercial construction world, with significant experience in commercial office, process piping, healthcare, site development, cannabis, mixed-use, industrial, retail, multi-family and education. Since establishing John Martin Companies in Chicago, both Jack and Marty have since expanded the business ventures into Wisconsin, California, New Mexico, Texas, Alabama, Missouri, Illinois, Ohio, Tennessee, Florida, Georgia and Colorado. Jack has a Bachelor’s of Science in Civil Engineering from Marquette University and Master of Real Estate from DePaul University.

Marty McDonnell serves as Owner and Partner of John Martin Companies, overseeing the firm development and operations across multiple markets. With more than 20 years of experience in commercial construction and real estate development, Marty has worked across a wide range of sectors including mixed-use, healthcare, childcare, cultivation, office, industrial, retail, hospitality, cannabis, and residential development.

At John Martin Companies, Marty is responsible for managing all phases of the development and construction process, ensuring projects move efficiently from concept through completion. His leadership helps guide project execution, financial oversight, and strategic growth as the company continues expanding into new markets across the United States.

Marty holds a Bachelor of Science in Civil Engineering from Marquette University and an MBA from Washington University in St. Louis.