Over the past 30 years greater attention has been focused on development of sustained or controlled release drug delivery. MEMS has been identified as one of the most promising technologies for the 21st century and has the potential to revolutionalize both industrial and consumer products by combining silicon based microelectronics with micromachining technology. MEMS based drug delivery devices have become commercially feasible due to converging technologies and regulatory accommodation. These products have the potential to completely control drug release, meeting requirements for on-demand pulsatile or adjustable continuous administration for extended periods. MEMS technology involves integration of mechanical elements, sensors, actuators and electronic elements on common silicon substrate through microfabrication technology.