Book excerpt: Forces of the Quantum Vacuum presents a number of theoretical approaches to Casimir, van der Waals and Casimir-Polder forces that have been fruitfully employed in mainstream research, and also reviews the experimental evidence for Casimir forces. Beginning with basic ideas in quantum mechanics and building its way to a sophisticated form of macroscopic QED, the book provides an inspiring training manual for graduate students to develop in a natural progression the ideas needed for modern theoretical research on Casimir forces.