OVERLAND PARK, Kan.—Marsh & McLennan Agency L.L.C. said Tuesday that it has acquired Overland Park, Kan.-based agency Haake Cos. for an undisclosed sum.

Haake, which has $11 million in annualized revenue and 70 employees, is the third in a series of acquisitions the New York-based Marsh Inc. subsidiary has made as part of efforts to build out its national middle-market agency platform.

Haake will become part of Marsh & McLennan Agency's Midwest growth strategy, said Chairman and CEO David Eslick, who described Haake as “a very nice operation” that “brings a great leadership team” to the Marsh agency.

In addition to personal lines insurance, Haake provides property/casualty insurance, risk control services and employee benefits to companies in a wide range of industries, with specialty practices in manufacturing, health care/life sciences, hospitality, environmental liability and alternative risk.

“It's just a really well-rounded organization that brought many different areas of strength that we thought we could leverage even further,” Mr. Eslick said.

In November, Marsh & McLennan Agency embarked on its acquisition strategy with the purchase of Insurance Alliance, a Houston-based agency with about $15 million in annual revenues. The next month, the agency acquired Paramus, N.J.-based agency NIA Group L.L.C, with annual revenues of $62 million.