With the increasing use of acoustical materials for purposes of interior finish, a number of additional uses have been found for these products. Cases are cited where the acoustical treatment has been made an integral part of the air conditioning system. The adaptation to improved lighting methods is discussed. Certain materials have such inherent architectural value that they are used primarily as interior finishes, with the acoustical function secondary. In the summary, suggestions are made to assist the architectural profession in taking advantage of these various adaptations. Details and photographs will be included.