Skip to content Sitemap


The History of McLennan Companies

McLennan Company was established in 1912 by William C. McLennan, a young Scottish bricklayer who had recently immigrated to the Chicagoland area. The company started as a contracting business, and throughout the 1920’s and 1930’s constructed over 5,000 homes.

This unique vision includes a 54-lot subdivision near Canfield Road and Devon Avenue that included the first all-gas houses in the city of Park Ridge.

The company expanded from masonry and contracting to subdividing, building, brokering and developing new concepts. They progressed to office buildings, store fronts, apartment buildings, and finally saw the need and opportunity to develop around O’Hare Airport. They were confidently moving into the era of large-scale commercial/industrial development in the O’Hare corridor, which is an area adjacent to the company headquarters first in Edison Park, and then in Park Ridge. McLennan pioneered the first fully fireproof multi-story apartment units, incubator commercial buildings and industrial parks, as well as the Chicago area’s very first residential condominium. These innovations kept the firm working hard and well engaged during the 1950’s and 1960’s. They anticipated the changes taking place in real estate and began buying land and constructing business parks; notably the Devon-O’Hare Industrial Park in Elk Grove and the Devon-Ellis Industrial Park in Bensenville in operation today.

Paralleling its founder’s professional accomplishments, the McLennan Company has been able to sense the path-of-progress and to generate viable opportunities within that path. As current President James D. McLennan, grandson of the founder has said, “Adaptability has been the key ingredient in these long years of remaining viable and vital. A big factor was choosing likeable, dedicated people to implement the company’s vision with skill and competence.” It is estimated that nearly 500 local employees have had a part in this rich company heritage, many with 15 years or more of commitment to the values and ethics instilled by the founder’s pioneering spirit and dedication to integrity. Additionally, there are highly loyal and very well pleased customers and business relationships that go back as many as 40 or 50 years. As McLennan has said before, “Buildings are our business, but it is the people we serve who are our real business. Our growth over 100 years has always been in direct proportion to our service to people.”

Today the company provides a variety of services to clients throughout Northwest Chicagoland, the greater O’Hare region, and Northern Illinois. They provide brokerage, sales and leasing, building management and investment services to multiple ownership groups. They oversee over 500 residential and commercial tenants, and manage more than 780,000 square feet of property, collecting close to $15 million from these properties each year. They have a network of trusted clients, skilled vendors and desirable business partnerships that make each project, account, or property valuable in its own way.

No one doubts that the McLennan Company will continue on its bright path as they continue to apply their skills and expertise to what it is they are known to do so well. Celebrating the fourth generation of family ownership and 100 years in business at the same time, there is excitement and change in the air. A century in business is an accomplishment very few companies achieve. But these people might have figured out the secret. As McLennan says, “You have to be a student of the culture. You’ve got to see the shifts and changes…You better embrace it or you’re going to be obsolete and you’re going to be history.” The current leadership at McLennan has no plans for that anytime soon. They strive on ahead while pursuing the goals of growth and diversification, always promising to keep their fingers on the pulse of all the markets that the McLennan Companies serve.