An attempt has been made in this work to develop a simple yet efficient sun tracking mechanism (SSTM) using smart shape memory alloy (SMA). This mechanism is directly activated by the sun dispensing with the requirement of an additional external source to power it. The SMA element incorporated in the SSTM device performs the dual functions of sensing and actuating in such a way as to position the solar receptor tilted appropriately to face the sun directly at all times during the day. The mechanism has been designed such that the thermal stimulus needed to activate the SMA element is provided by the concentration and direct focusing of the incident sun rays on to the SMA element. This paper presents, in detail, the design and construction adopted to develop the functional model that was fabricated and tested for performance. © 2011 American Society of Mechanical Engineers.