In recent years there has been a mounting chorus of criticism about building codes. They have been blamed for increased construction costs, inability of new materials to gain a footing in the construction field, and numerous other undesirable conditions. Statements about them have sometimes been so unfavorable as to cause concern among thoughtful people that public confidence in measures to assure public safety would be seriously undermined. Of late, a slight reaction is beginning to appear to the effect that, after all, many codes are doing a fair job. Whatever the magnitude of their merits or defects, it becomes apparent to anyone who gives much attention to the matter that here is a subject of much importance to the construction industry as a whole and currently to that considerable part that is giving its best efforts to relieving the shortage in housing. The background is simple. Experience has proved that government must act in protection of the public to control the operations of the ignorant, the incompetent, and the unscrupulous in the construction field. Fire, collapse, and other sources of injury and even death traceable to imperfect construction occur frequently enough to remind us that trouble can occur even when regulations are in effect to prevent it. What could happen in the absence of such regulations, or in the event of regulations so weakened that they become inadequate, can readily be imagined. So the state steps in, exercises its police power, and attempts to furnish reasonable safeguards. Workers in the field of building code improvement become accustomed to periodical rediscovery of the subject by others and recurrent demands for sweeping changes which will somehow accomplish a variety of things. They welcome these manifestations of interest for, when no serious disasters are occurring and no economic convulsions are creating demands for drastic measures of all sorts, relatively little interest is displayed in the subject by the general public. It is not always easy, however, when interest is keen to explain the nature of the problems that must be faced and the complicating factors that must be satisfactorily adjusted before a quickening in the rate of progress of improvement is possible. The problems are in part technical,