The Western Design Center (WDC), located in Mesa, Arizona, is a company which develops intellectual property for, and licenses manufacture of, MOS Technology 65xx based microprocessors, microcontrollers (µCs), and related support devices.

Beyond discrete devices, WDC offers device designs in the form of semiconductor intellectual property cores (IP cores) to use inside other chips such as application-specific integrated circuit (ASICs), and provides ASIC and embedded systems consulting services[2] revolving around their processor designs.

WDC also produces C compilers, assembler/linker packages, simulators, development–evaluation printed circuit boards,[3] and in-circuit emulators for their processors.

The 65C02 reduced the power consumption, improved noise immunity and added some new instructions.

The 65C816 was later chosen as the core of the Ricoh 5A22 processor that powered the Super Nintendo Entertainment System.