Abstract: Security gate apparatus for securing building openings in the nature of window and door openings are disclosed; and comprise a security gate including gate-carried locking means which, while of particularly sturdy construction and effective to render it extremely difficult if not impossible as a practical matter to open the security gate from without the building opening, are nonetheless virtually foolproof in operation, and which are very readily and conveniently openable from within the building, even by those of somewhat limited mental and/or physical capacities, in readily apparent manner to thereby insure virtually immediate exit from the building through the building opening for the building occupants in emergency situations.