The humble oscillator is a ubiquitous circuit, contained in many electronic systems. A temperature independent, fully monolithic, CMOS oscillator that has a reduced process sensitivity is presented. Temperature independence is achieved via a novel zero temperature coefficient current source and, when implemented correctly, the primary source of deviation in the oscillation frequency is the process variation in the mobility of silicon. The oscillator is implemented in a 0.7 μm analogue CMOS process.