Disclosed is a holster for a weapon such as a handgun which includes a body defining a cavity for receiving and holding the weapon, a hood assembly pivotably connected to the body, the hood assembly pivotable between a closed position for securing the weapon within the body cavity and an open position for removal of the weapon, a locking mechanism securing the hood assembly in the closed position when a weapon is held in the body cavity, a release mechanism associated with the locking mechanism for releasing the hood assembly to the open position for removal of the weapon, and a mechanism for automatically pivoting the hood assembly to the closed position and thereby automatically engaging the locking mechanism upon insertion of the weapon into the body cavity, wherein the locking mechanism is biased to a locked configuration when the weapon is held in the body cavity.