Stephano Slack Announces Strategic Growth Investment from Madison Dearborn Partners

Partnership with Madison Dearborn Partners adds strategic capital and industry expertise to further augment Stephano Slack’s capabilities as a leading provider of tax, audit and advisory services

WAYNE, Pa.--(BUSINESS WIRE)--Stephano Slack, a premier accounting and advisory firm, today announced a strategic growth investment from funds managed by Madison Dearborn Partners (“MDP”), a leading private equity investment firm based in Chicago, with additional participation from co-investor Norlantic Capital. The partnership will accelerate Stephano Slack’s strategic plan and support its long-term vision of investing in talent, embracing innovation, and creating opportunities for clients and team members alike.

Stephano Slack will continue to be led by its existing leadership team, including CEO and Managing Partner Michael Stephano. The firm will continue its focus on delivering excellence to a growing client base while executing on the firm’s operational and growth priorities. Jim Brady, a forty-five-year industry veteran and former COO of Grant Thornton, will join Stephano Slack as Executive Chairman. Jim brings a proven track record, from Grant Thornton as well as thirty years at Deloitte, of developing talent and scaling accounting and advisory organizations through periods of transformational growth.

“We were first introduced to Stephano Slack by Jim Brady, and, from our initial meeting, it was clear that Michael and his team have built a high-quality, growth-oriented business, ideally suited to MDP’s decades of experience in scaling professional services platforms with strong operational advantages and broad addressable markets,” said Vahe Dombalagian, Managing Partner and Co-Head of Financial Services at MDP. “We look forward to partnering with Michael and Jim to accelerate the growth of the platform, deepen service offerings, and broaden the firm’s geographic reach into new markets.”

Founded by Michael Stephano in 2004, Stephano Slack provides a full range of tax, audit, outsourced accounting, and advisory services to a diverse base of middle-market clients. Stephano Slack was recently named one of Accounting Today’s Fastest-Growing Firms of 2026, highlighting the firm’s consistent track record of growth and its culture of excellence. Over more than two decades, Stephano Slack has remained committed to a client-first approach while delivering sustainable growth and successfully integrating seven strategic acquisitions.

“Our partnership with MDP, a firm that understands and embodies our commitment to exceptional relationship-driven client service, adds a compelling new growth driver to the Stephano Slack platform,” said Michael Stephano, CEO and Managing Partner at Stephano Slack. “MDP’s support will pave new avenues for Stephano Slack to grow and diversify our platform and will foster opportunities for both our clients and employees.”

“I’m eager to get started working alongside Michael, whom I have known personally and professionally for years, as the leader of a well-respected and growth-oriented firm,” said Jim Brady, incoming Executive Chairman of Stephano Slack. “I’m confident that our combined operational experience and passion for identifying opportunities and building talented teams will add to Stephano Slack’s strengths and position the firm for continued success.”

Following the close of the transaction, Stephano Slack will operate in an alternative practice structure. Stephano Slack, LLC, a licensed CPA firm, will provide attest services, and Stephano Slack Advisory, LLC will provide tax, business advisory and other non-attest services.

Koltin Consulting Group advised MDP, and Paul, Weiss, Rifkind, Wharton & Garrison LLP, Kirkland & Ellis LLP, and Vedder Price P.C. provided legal counsel to MDP. Leelanau Management advised Stephano Slack, and Pierson Ferdinand provided legal counsel to Stephano Slack. Freshfields LLP provided legal counsel to Norlantic Capital.

About Madison Dearborn Partners

Madison Dearborn Partners, LLC ("MDP") is a leading private equity investment firm based in Chicago. Since MDP's formation in 1992, the firm has raised aggregate capital of more than $36 billion and has completed over 160 platform investments. MDP actively invests across three dedicated industry verticals, including financial services, healthcare, and technology & government. Drawing on deep industry and operational expertise, MDP works closely with management teams to drive value creation and operational improvement across its portfolio. For more information, please visit www.mdcp.com.

About Stephano Slack LLC

As a leading accounting and advisory firm, Stephano Slack offers a full range of tax, audit, outsourced accounting and advisory services to clients. Specializing in privately owned, middle-market companies, the firm offers timely, reliable financial information, along with creative business and tax strategies that help clients achieve their financial goals. Stephano Slack is dedicated to fostering strong client relationships through industry events, webinars, seminars, and newsletters. For more information, please visit www.stephanoslack.com.

About Norlantic Capital

Norlantic Capital is a specialized, cross-border private equity firm that exclusively targets the U.S. middle market – one of the most dynamic, diversified, and growing segments of the asset class. It provides a new generation of alternative investors exposure to this market by investing in top-tier managers through its broadly diversified fund, complemented by its direct and custom investment strategies. Backed by leading institutional investors, Norlantic is headquartered in New York with strategic operations in Dublin. For more information, please visit www.norlantic.com.