Abstract: A knife accommodating interchangeable blades. The knife includes a blade having a tang extending from its base, and an elongate handle having a front, blade-receiving region and an opposed back region. An elongate lever having opposed pivot and locking points is attached at its pivot point in the back region of the handle for swinging toward and away from a locked position in which the lever is axially aligned with the handle. The lever provides, adjacent its pivot point, a cammed surface dimensioned to engage a spring arm within the handle, thus to lock the lever in its locked position. The blade tang is securely held within a cavity defined in part by the locking point of the lever, with the latter in locked position.