Dependable embedded systems are an indispensable technology in today`s information society and used in more and more safety-critical applications. One of the main challenges of this wide spread usage is the increasing complexity which makes it very difficult to reach the necessary dependability.Integrated architectures, building execution platforms from a set of pre-validated hardware and software components, promise a solution for the stated problem. A core technology of such an architecture are partitioning OSs (Operating Systems) which are able to execute multiple software components on a single processor while guaranteeing that these components cannot influence each other. This shall hold for both, the temporal and the spatial domain.This book shows a possible implementation of such a partitioning OS on top of a RTAI (Real Time Application Interface) real-time Linux system. An existing prototype implementation, developed within the EU funded DECOS (Dependable Embedded Components and Systems) project, is evaluated and improved regarding partitioning capabilities.This book is written for: computer science researches and practitioners; graduate students.