The radical technological improvements, the low cost and the popularity of Intel processors are leading the major multiprocessor system integrators to design and build the new parallel systems based on Intel microprocessors, which are interweaved historically with the Windows operating system. In this paper, we present the development of a kernel-mode device driver that performs efficient scheduling of parallel applications on the Windows 2000 operating system. This environment can easily be used as a platform for developing and evaluating scheduling policies on multiprocessors systems running Windows 2000. We review and evaluate the basic primitives and mechanisms in kernel-mode, which we used in our implementation, introducing our own solutions wherever is necessary. Our results demonstrate significant performance improvements and scalability enhancements over the native Windows 2000 scheduler, indicating the integration of such a subsystem in the Windows kernel.