The effect of poor posture on appearance is obvious to anyone who will look about him on the street. Not so obvious are the ways in which it may cause fatigue, aches and pains and improper functioning of internal organs. This is why we use ‘‘X-Ray’’ drawings as our illustrations. Turn back to the drawings on page 2. See how (in B) the spine and leg bones are straight enough to support the body weight with the least possible muscular effort. When poor posture (A) throws these bones out of line, the muscles must work harder to hold the body up, and an extra strain is thrown on the joints and ligaments. This is why we speak of “body balance’’; good posture is achieved when the weight is well balanced on the bony structure. Correct posture, once it becomes a habit, is the easiest posture to maintain. Now look at the drawing on the opposite page to see what happens to the internal organs. The pelvis is tilted forward (compare its posi- tion in A, page 2, with the dotted line) and the abdominal muscles sag outward. The chest is flattened, crowding the lungs and heart. The diaphragm, the dome-shaped muscle which sep- arates the chest and abdomen, is forced down, pushing the stomach and other organs out of place. This crowding may interfere with breath- ing, circulation, digestion, or other functions, causing many of the vague complaints which distress otherwise healthy men,, women and children.