An adjustable leash with automatic slack take-up assembly comprising a pulley buckle and cam buckle. The lead end of the leash strap is affixed to a top opening of the pulley buckle, and the leash body is movably threaded in operative order through a first opening of the cam buckle, a bottom opening of the pulley buckle, and a second opening of the cam buckle. In operation, a user maintains a grip at all times on the lead handle. The user depresses the spring loaded tab with the users other hand. While depressing the spring loaded tab, the user pulls a pull tab on the cam buckle with the second hand to either lengthen or shorten the device. Once a desired length has been formed, with automatic slack take-up as the leash length is adjusted, the user releases the spring loaded tab to lock the device into position.
