The requirements of an art museum to insure control of light, aircleaning, temperature and humidity are briefly stated and illustrated by means of diagrams. The core where works of art are stored and exhibited should be buffered against the external environment by surrounding it with a corridor on the outside of which are situated offices, public rooms, work areas, which do not require such optimum conditions of temperature and humidity. Air leakage to exhibition areas from less controlled areas may be minimized by partial air locks and maintenance of higher air pressure in the core than in the corridor.