In late 1959, Howard M. "Budd" Post, a young resident engineer with the Florida State Road Department, was offered an opportunity by a prominent developer to help create Miami Lakes, the first planned "new town" in Florida. Post, with fellow engineers, George G. Mooney, Robert P. Schuh, and John D. Buckley, established a new corporation to handle the assignment. Each contributed to the $500 initial working capital, and Post's boyhood pal, Bob Schuh, became the first full-time employee as Robert P. Schuh & Associates was born on February 29, 1960.

By 1961, Post, Buckley, and Mooney had joined full-time as principals, and the company's name was changed to Post, Buckley, Mooney & Schuh. Services encompassed not only civil engineering assignments, but also sanitary engineering, highways, and bridge work. In 1963, the firm's founders created an employee trust that enabled employees to buy into the firm, creating a positive means of motivating and retaining key employees that remains today. Following Mooney's departure from the firm due to health reasons, Alex M. Jernigan became a principal, and in 1970 the firm was renamed Post, Buckley, Schuh & Jernigan, Inc. (PBS&J). The PBSJ Corporation was formed in 1973 as the stockholding entity over PBS&J and future subsidiaries.

During the 1970s, the company began to expand beyond its South Florida base, opening offices in other parts of the state and increasing in size and technical strength. Expansion outside of Florida began during the 1980s, and by the end of the 1990s, the company’s offices spanned the nation from coast to coast and was doing business in overseas. The company’s service offerings also increased significantly over these decades, and the company developed a solid reputation for excellence in environmental sciences, planning, landscape architecture, architecture, program management, and associated disciplines to complement its strong, legacy engineering and construction management services.

Historically, the company’s expansion has always been carefully based on realistic market opportunities. This growth has been predominately through organic means complemented by strategic acquisitions intended to increase both geographic presence and technical capabilities. Today, The PBSJ Corporation has nearly 4,000 employees and 80 offices located throughout the United States and abroad. The Corporation has four primary subsidiaries: PBS&J; PBS&J Constructors, Inc.; Peter R. Brown Construction, Inc.; and PBS&J International.