Book excerpt: This book examines logistics systems in an integrated way. Its goal is to describe and show how to find rational structures for logistics systems considering all the relevant aspects. Building on an understanding of the simplest logistical system with only one origin and one destination, the book treats problems with many origins and one destination, many destinations and one origin, and many origins and many destinations; this is done for systems with and without transshipments. The solutions and methodologies presented in the book are particularly helpful in instances where detailed data are not available and when time is of the essence.