RESEARCH TRIANGLE PARK, N.C. … Independent research institute RTI International will acquire a Cary environmental research operation from Midwest Research Institute.

Terms of the acquisition, which is expected to close by June 30, weren’t disclosed.

The deal marks the second acquisition by RTI, formerly Research Triangle Institute, in four months after never having pursued an external growth strategy during its 43-year history. In February, RTI bought Health Economics Research of Waltham, Mass.

“Part of our mission is to expand our core competencies, and that is what these deals do,” RTI spokeswoman Jill Denning says.

Kansas City, Mo.-based Midwest Research, which is a nonprofit operation similar to RTI, approached RTI officials recently and offered to sell its 20-person Cary environmental operation, Denning says.

The Cary office assists the Environmental Protection Agency in monitoring air pollution and developing emissions standards. RTI also works in that area and plans to combine the two operations into a new Center for Environmental Engineering, which will consist of nearly 115 people.

RTI is an independent, nonprofit organization dedicated to conducting research in the fields of health and medicine, environmental protection, technology commercialization, decision support systems, and education and training.

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