This paper analyses the influence of postal architecture's quality assurance from the view point of client side. Postal architecture is very unique tradition, having both clients and architects function in the organization. Postal architecture was born in 1885, with over 130 years' historical accomplishment. The era of postal architecture has been divided into 4 phases; 1) the era of in-house designers who lead building projects, 2) era of specialists, 3) era of project management, 4) era of externalities and privatization. This paper analyses the changing role of clients and how the environment society has been influenced these changes.
