Neutral safety switch , burned fusable link wire or possibly the ignition switch down on the column is out of adjustment. If you have a tilt column try moving up and down all the way to see if it will start if it does your switch is not adjusted correctly or you may have a broken ignition rack inside the column. The ign. rack is what mechanically pushes the rod to activate the switch when you rotate the lock cylinder .. Check the small wire going to the starter for power when the key is in the start position. BE SURE THE CAR IS SAFELY ON STANDS.