A multi-functional writing instrument which includes a combination pocket clip and stylus for input devices, such as personal digital assistants. The writing instrument includes a body having a cap portion, and the combination clip member and stylus having first and second ends, wherein an actuator tip is mounted to the second end and the clip member is mounted to the cap portion and slidably movable with respect thereto. The clip member is slidably movable relative to the body between a clamping position, for attachment to a pocket, and a stylus position, where the actuator tip of the clip member is extended beyond one end of the instrument's body enabling engagement with a touch screen. The instrument allows the user to conveniently switch from writing on conventional media, for example paper, to inputting data in a personal digital assistant.