For years, the business of servicing commercial real estate properties was dominated by just two firms.

Now DTZ, with its $2 billion takeover of Cushman & Wakefield, is betting that it can break into the top ranks, a plan that has been in the works for some time.

If completed, the transaction would create a much stronger competitor to the two giants of commercial real estate services, the CBRE Group and Jones Lang LaSalle. The newly combined company, which would take the better-known Cushman & Wakefield name, would have more than 43,000 employees across more than 50 countries.

“The companies have remarkably complementary skills and reach in different geographies — whether in New York, London or Shanghai, this will be a formidable combination,” Brett White, the executive chairman of DTZ, said in a statement. “While breadth and depth are important to serve clients, it’s not just about size. It’s also about local expertise and deep customer service, which are strong traits of Cushman & Wakefield and DTZ, and ultimately what will differentiate us going forward.”