The question discussed is what should be preserved and how is this to be accomplished. Any building worthy of being preserved is presumed to have a functional usefulness. The additional criteria are intrinsic aesthetic, religious, and scenic usefulness. The unique character of a structure is not sufficient grounds for maintaining it. Discussion focuses upon degrees of value. Economic necessity can limit choices; there is a level of uncertainty in private judgments. A sketchy outline of the means of preservation is presented. Each particular problem demands individual treatment. One needs to consider the loss of restoring a building to its original style when additions in fact add to the contemporary value. At times, to preserve the landscape, it is appropriate to preserve only the facade.