A security device is disclosed which inhibits opening of a door or window. In one form the device (10) comprises an element (14) which fits in a floor at a place over which the door or window must pass when opening. A stop element (12) has a spigot (16) which fits in the sleeve (20) of the element (14). The stop element (12) when fitted into the sleeve (20) protrudes above floor level and lies in the path of travel of the door or window to prevent it being opened. In another form the security device is remotely operable. In still further forms the device includes audible alarm means to warn of attempted door or window opening.
