This thesis is a documentation of research, evaluation, and design for the Pahlavi National Library project for Tehran, Iran. The written section of the thesis externalizes the most critical issues and concerns gathered from the evaluation of traditional architecture in Iran and the examination of the needs of libraries in general. These two factors were combined with the given program to generate the design of the library. A conceptual framework of what a National Library should be is established in conjunction with a set of architectural criteria employed for decision making. The project requires a solution at three different levels: that of the building itself as a library; the building's adaptability in the context of a culture, and, especially, the building's relationship to the climate. On the whole, the design of this thesis has mainly generated from two major objectives. Primarily, to design a functional and social environment whose plan incorporates and reflects an understanding of traditional architecture--a facility that is adaptive for its purpose, its users, and its environments. Secondly, to document the process which has led to the design solution. / Master of Architecture