Architecture, design and strategy firm Nelson Worldwide has merged operations with Daroff Design Inc + DDI Architects, an interior design and architecture firm headquartered in Philadelphiia's Center City neighborhood. 

With almost 50 years of history as a certified Woman Business Enterprise, DDI joins the Nelson team with shared values.

“We are extremely excited that Karen Daroff and her team will be joining Nelson,” Nelson Worldwide Chairman and CEO John “Ozzie” Nelson Jr. said in a statement. “Since launching Daroff Design almost five decades ago, she has led the firm to national and international prominence and has received many accolades along the way. I am looking forward to her having the opportunity to continue her legacy alongside our team.” 

Nelson has previously acquired Philadelphia-based companies such as H2L2, Space Design, Cope Linder and Brinjac Engineering and is continuing to scale. As part of a long-term strategic growth plan for Nelson, the merger will combine the firm’s strengths to address its clients’ challenges. DDI’s creative team, combined with Nelson's geographic reach, will allow the firm to expand and strengthen its ability to deliver exciting and emotionally connected experiences within the built environment. 

DDI joins Nelson with an expansive project portfolio across the workplace, hospitality, multi-family and public sector. The firm specializes in facility programming, master planning and design. Some of DDI’s clients include Comcast, NBC Universal, The Durst Organization, Vanguard, Disney, JetBlue, Loews Hotels, St. Regis, Ritz Carlton, PIDC, Sheetz, MGM Resorts, Parx Casino and Harrah’s.

“Nelson and DDI share many of the same values and are aligned both in spirit and our strong commitment to hands-on client service and design excellence,” said Karen Daroff, IIDA, president and design principal at DDI. “When approaching this merger, it was important to identify a company with a large and dynamic national presence to better serve our clients. I am also personally thrilled to have the opportunity to collaborate with team members nationally and service our clients with a national footprint. This is an amazing opportunity to integrate our teams, bring together our shared visions and to have a strengthened presence in our merged Philadelphia headquarters.”

Nelson will add 25 employees from the DDI team alongside Daroff. Daroff will provide hands-on leadership for Nelson’s hospitality practice and become a senior leader within the firm’s Philadelphia interior design team.