This monograph offers a comprehensive analysis of the architecture and architectural decoration of the porticoes and exedrae in the Forum of Augustus in Rome. Integrating a detailed examination of the preserved masonry structures with an in-depth study of hundreds of architectural elements, the volume presents updated reconstruction proposals for the elevational orders, framing systems, and roofing schemes. The research re-evaluates the complex design syntax, combining classical and Hellenistic Greek models with late Republican Roman-Italic traditions to define the unique Augustan architectural language. Through a rigorous tipological and stylistic assessment of capital types, entablatures, and attic elements, the study sheds new light on the construction site's chronology, labor organization, and active stonecutters. Ultimately, this work provides a fundamental scientific framework for understanding Augustan monumental planning and serves as a vital reference for the preservation and study of Imperial Roman architecture.