Provided is an ankle-foot orthotic device and method for preventing foot drop of a person wearing footwear. The device includes an elongated member adapted to extend along an anterior portion of the lower leg and conforms to a portion of the dorsal surface of the foot. The elongated member is further adapted to secure to an upper outer region of the person's footwear. Securing the device to the lower leg and footwear of a person maintains the foot in a dorsiflexion position. The elongated member may include an upper portion positionable relative to an intermediate portion providing an ankle-foot orthotic device variable in length.