Gelasio Caetani, the Italian ambassador in 1924, was a trained architect and engineer and reputedly was involved in the design of the embassy from its site selection to its interior decoration. Caetani and the architects of record, Warren and Wetmore of New York, followed Italian Renaissance models both in the embassy's three-story elevation and in its plan. Proportions and details are more historically correct on this building than on its more eclectic neighbors. As in Italian Renaissance mansions, the ground story is decidedly separated from the piano nobile by a wide belt course. Projection of the bracketed triangular pediments of the main-story windows—based on those of the Palazzo Farnese in Rome—gives sculptural relief to the smooth limestone walls. The two main stories are integrated by an elaborate entrance motif with the segmentally pedimented second-floor window set within the broken triangular pediment of the doorway. The rectilinear main block is separated from the chancery by a single-story connector on the north, whose windows originally were open onto an arcaded loggia overlooking the square courtyard. The chancery wing on the east was part of the original design but enlarged about 1930.