Abstract: A lockable sliding door is described. A ratcheted track allows the movable panel of the door to be selectively locked in both closed and vented positions. A lever is positioned along a midpoint of the movable panel to allow for the easy engagement of the locking mechanism. Further, the locking mechanism is carried on the movable panel. The technology is configured to allow the sliding door to be locked in various configurations, with the door partially opened, completely open, or completely closed. The technology may also be utilized on windows or any other architectural features with a slide-to-open and close design.