Stambaugh Ness and Zweig Group announced a merger to form SNZweig, a private equity-backed professional services and advisory firm for architecture, engineering and construction business clients.
The joint firm will operate under an alternative practice structure. San Francisco-based private equity firm Aphias Capital is making a majority investment in SNZweig Advisors, which will offer the firm's non-attest services. Stambaugh Ness will operate as an independent CPA firm providing audit and attest services. The deal is expected to close later this fall.
Stambaugh Ness, based in York, Pennsylvania, is an Accounting Today Mid-Atlantic Regional Leader, reporting $50.5 million in revenue, with 32 partners and 187 employees. Zweig Group is based in Fayetteville, Arkansas, with an additional office in Dallas. The two firms first partnered in March 2025.
"This is a defining moment for the AEC industry," Steven Hake, CEO of SNZweig and former president and CEO of Stambaugh, said in a statement. "SNZweig represents more than the combination of two organizations; it represents a new opportunity for the industry. Together, we've designed something unprecedented; equipping firm leaders with insight, confidence and support to grow stronger and more resilient."
Citizens Capital Markets & Advisory served as financial advisor and Vedder Price as legal counsel to Stambaugh Ness and Zweig Group. Lazard Frères & Co. served as financial advisor and Kirkland & Ellis as legal counsel to Aphias. Terms of the deal were not disclosed.
"Stambaugh Ness and Zweig Group have each spent decades earning the trust of architecture and engineering firms, and their partnership has already shown what the integrated model can do for clients," Rob Wolfson, founder and managing partner of Aphias Capital, said in a statement. "We are proud to partner with the SNZweig team to create the market-leading professional service provider and knowledge partner to AEC firms."
