Preface. 1. Introduction and Overview. 2. Background and Fundamental Results. 3. Processes with General State Space. 4. Processes with Countable State Space. 5. Sample-Path Stability. 6. Little's Formula and Extensions. 7. Insensitivity of Queueing Networks. 8. Sample-Path Approach to Palm Calculus. Appendices. A. Ergodic Theory and Random Marked Point Processes. B. Limit Theorems for Markov and Regenerative Processes. C. Stability in Stochastic Models. References. Index.