There is an accordion door in our basement, blocking one large room off from the rest of the basement (well, it's supposed to block...)
This had to be installed after La Doof Kitton stole paintbrushes and little lead miniatures and bits of important things (repeatedly), in spite of attempts to put them up out of Kitty reach. (We have determined that the only place out of kitty reach is stapled to the ceiling, at least 4 feet from any jumping surface and dangling less than 2 feet from the celing).
La Doof Kitton proved quite adept at opening the magnetic closure on the accordion door. There is a knack to this, one merely beats on the edges of the door until the door sighs audibly, stares at the kitty in frustration and leaves itself agape for a moment. In that moment when the door is barely agape, one must merely get one retractable claw (must have retractable claws for this, that's why it doesn't work for humans trying to open locked doors) in the wee opening. Then the tail becomes the "lever long enough..." and it will eventually pry open.
The Mr. decided that he must better protect his hobby objects (especially since I recently retired a very lovely, poofy, powder brush for him to use (in something involving words like "drybrushing" and "flock" and "terrain") which La Doof Kitton wishes to have an illicit affair with) so he installed a hook-and-eye style latch on the door, about 4 feet off the ground.
Obviously, since mounted on a door, this device does *NOT* meet the standards to keep it out of kitty reach...
Last night, as in all the previous nights, we made sure the hook was firmly hooked and the eye was firmly screwed into the frame, fastened the magnetic latches and went to bed. And we awoke to a door open precisely the width of one kitty. So we gave up and resorted to drastic measures.
Currently, there is a sheet of plywood lightly tacked over the opening to the large opening into the basement. To enter the lair of the hobby supplies, one needs only to grab a claw hammer, pry up one nail, swing the plywood out of the way, and one can enter.
La Doof Kitton hasn't yet figured out how to substitute a retractable claw for a claw hammer but he is working on it.