The easiest way to control any complex application is through voice command and IVORY has developed a standard plug-in board for personal computer (PC)-based voice recognition applications. It includes specially developed software with sophisticated noise cancellation algorithms, providing highly reliable real time recognition of commands in noisy environments. Recognition of commands is completely independent of the speaker. The hardware platform is highly flexible and can easily be adapted to computer-based industrial control systems, where noise cancellation is of particular benefit. The noise-cancellation sub-system can also operate standalone, to output clean speech. With software changes, the board can also be used for other signal processing applications. The board is designed around general purpose hardware, using a DSP (digital sound processor) core and a standard PCI interface. For speech recognition, the software has been developed to ensure speaker-independence with no training, allowing use in public areas and for multiple-user access. Large, pre-defined word-sets can be downloaded to firmware, allowing simple tailoring of the application (for example by changing the language). Noise cancellation algorithms separate speech and noise, even in a games arcade where background noise can reach about 90 dB. The board has been optimised for the professional PC market, but could also be easily adapted to non-PC hardware environments using different interfaces and interconnects. With simple software modifications, it could run signal processing software for other applications.