Chicago-based professional staffing firm Addison Group acquired HireStrategy, a professional staffing firm based in Reston, Va., that recently landed on the list of Best Staffing Firms to Work For. The transaction closed April 18 and terms of the transaction were not disclosed.

HireStrategy's brand will remain initially, and will transition to the Addison brand in the future. HireStrategy’s executives will remain with the firm.

Founded in 2000, HireStrategy counts more than 100 internal employees and more than 500 employees including contractors. Its core practice areas include technology, finance and accounting, sales and marketing, recruiting and HR, and administrative. The firm has three offices: Reston, Va.; Washington, D.C.; and Bethesda, Md.

Addison ranks No. 90 on the Staffing Industry Analysts’ list of largest U.S. staffing firms. It is a portfolio company of private equity firm Trilantic Capital Partners. Trilantic acquired Addison, the first staffing firm in its portfolio, in October.

“HireStrategy, a local market leader, will bring invaluable experience and influence to the Addison Group brand,” said Thomas Moran, CEO of Addison Group. “Its expertise in the mid-Atlantic region and the Washington, D.C. market, along with an excellent management team, make this partnership an obvious choice. I am excited about what the future holds for both Addison and HireStrategy.”