The ideal operating room for the plastic surgeon need not necessarily be large, since it requires less work to render it aseptic. Furniture and possibly amphitheater accommodation are always a means of infection unless scrupulously cleansed, a task of time, difficult at best. The room should be provided with large windows, with facilities for the introduction of the air from without. Two doors, and those well fitted, are all the room should have—but one being used, if possible. =The Walls.=—The walls should be of plaster, smoothly laid and well painted, so that they may be readily washed down with antiseptic solutions—a daily morning rule. Glass or tiled walls are much used now and add considerably to the appearance and safety of the room, as plaster in time will crack, while the paint, owing to the heat of sterilizers or steam, often creeps and blisters, exposing an absorbing surface which readily wears down, exposing parts inaccessible for even acute cleanliness. =The Floors.=—The floors of these rooms are now usually laid with tile mosaic or marble or a composition resembling linoleum. The base should be curved and all corners sloped off to improve drainage and to keep off dust and dirt. =Skylight.=—A skylight of metal and glass is a valuable accessory. It should be fixed or never permitted to be opened during an operation. =Disinfection.=—Spraying the room with an antiseptic is hardly necessary, since all germ life descends to the floor and can best be removed by washing with a 1-1000 bichlorid solution. Should it be necessary to perform an unusually extensive operation in a private house, the room must be cleared of all furniture, pictures, drapery, and carpet. After plugging up the crevices in the windows and doors it should be well fumigated either with sulphur candles, as now commonly furnished, or, better, with formaldehyd. The superiority of formaldehyd as a disinfecting agent is now well established. An illustration of an apparatus, largely doing away with the difficulties and dangers encountered in the use of the older and ordinary styles of the pressure or nonpressure type, is shown in Fig. 3. The main difficulty with these has always been their almost inaccessibility for cleansing purposes, and in such where this is not the case, the size of the aperture has been made so small that the inside could not be reached. In the pressure apparatus the tops are bolted on, making them exceedingly difficult to remove, with the result that the necessary cleaning was not properly attended to. The corrosive action of formaldehyd gas is such that under these conditions any apparatus would soon become useless.