Local practitioner Juan G. Landry (1892–1966) called in Rathbone DeBuys to work on this austere PWA Moderne building with its many incised ornamental reliefs. Landry was born, educated, and worked in New Orleans, including for DeBuys, before becoming a partner in the firm of DeBuys, Landry and Theard. Arriving in Hattiesburg in 1926, he partnered with Carl E. Matthes in 1937. The limestone post office’s symmetrical five-part facade features stout pylon-like elements flanking three deeply set entrances in the central section. Typical of PWA buildings are the many aluminum elements, from doors and windows to lighting standards. Inside, the L-shaped lobby retains its polychromatic marble flooring and wainscoting, stenciled ceiling ornamentation, and octagonal light fixtures, as well as marble work tables.
Across the corner at 200 W. Pine Street the former post office (1910, James Knox Taylor, Supervising Architect of the U.S. Treasury) is now county offices. A flared red terra-cotta tile roof adds an exotic touch to the marble-clad Italian Renaissance Revival design, with a central entrance with columns in antis, paired brackets, and metal ventilation grilles.