Our Firm

Engineering Excellence.

Since our inception in 1981, O’Donnell & Naccarato has transformed from a 3-person structural engineering firm into a national presence with over 120 dedicated professionals operating from eight strategically located offices. This journey reflects our unwavering commitment to our core values of communication, quality, innovation, growth, and collaboration.

O&N is a trusted partner for structural solutions across all sectors of the construction industry. With a diverse portfolio of projects spanning every corner of the United States, we offer local expertise with a national reach.

Our depth of experience and limitless creativity are the cornerstones of our approach. Whether crafting innovative designs for new structures or breathing new life into existing ones through expansion, renovation, or restoration, our aim is singular—to help property owners realize the highest and best use of their assets.

As an employee-owned structural engineering firm, nearly all our staff are members of the ESOP, reflecting our deep ownership mindset. This pride in ownership permeates through every aspect of our work and is evident in the care we dedicate to our projects.

Our Professional Engineers Are Registered in 49 States Across the U.S

1,000

Averaging Over 1,000 Projects Annually in Every Major Construction Sector

Over 2 Billion SF of BIM Structures Produced Since 2006

$6B

Annually Responsible for $6+ Billion in Construction Value

8 Offices Nationwide

Our History

O’Donnell & Naccarato was founded by Bill O’Donnell and Pete Naccarato, whose dedication to building long-lasting client relationships became the cornerstone of our firm’s success. With a passion for delivering quality and creative engineering solutions, they ensured that every project not only met client needs but also strengthened those partnerships. This vision and commitment remain deeply embedded in our firm’s culture and continue to drive our growth and excellence today.

O’Donnell & Naccarato Founded

1981

Provided structural engineering services for the Wyndham Atlantic City, formerly known as Tannen Tower. This 32-story hotel and parking structure was constructed using cast-in-place, post-tension concrete with a precast concrete alternative. This project marked the beginning of our proficiency in high-rise developments.

First Major Highrise Project

1983

Our firm made a significant leap forward by adopting AutoCAD, one of the most advanced computer-aided design tools at the time. This early embrace of cutting-edge technology allowed us to enhance precision, streamline workflows, and produce more efficient, innovative structural documents.

O’Donnell & Naccarato Adopts AutoCAD

1988

Completed our first major healthcare project at St. Christopher’s Hospital for Children in Philadelphia. This 183-bed, 310,000-SF replacement hospital marked the beginning of a long-standing commitment to healthcare design.

First Major Healthcare Project

1989

Trusted partners in our clients’ success stories.

We are committed to deliver exceptional structural engineering solutions, while providing value to our growing family of clients, employees, and communities across the country.

Meet Our Team