WSP Global Inc. (TSX: WSP) is buying private equity-backed Focus Group Holding Inc. for an undisclosed amount.

Calgary, Alberta-based Focus Group provides engineering services in western Canada to the energy and infrastructure markets. Montreal-based WSP is an engineering consulting firm.

KRG, headquartered in Denver, is a private equity firm that has $4.3 billion in capital under management. The firm invested in Focus Group in from its third fund and has completed nine add-on acquisitions. In January, the company bought an engineering firm, Hunter Laird Engineering Ltd. The firm's other investments include Trafficware Group Inc., which recently purchased PSI Acquisition LLC, and ATI Physical Therapy Holdings LLC, which picked up SCP Physical Therapy and Dwight Orthopedic Rehabilitation in December. 

Harris Williams & Co. acted as Focus' financial adviser, while Stikeman Elliott LLP provided legal advice.

M&A between companies that provide services to the oil and gas industry has been heating up. Recent deals include Arsenal Capital Partners' purchase of Kel-Tech Inc., and Access Midstream Partners LP's deal for natural gas compression assets