The environmental and chemical sciences are ever more reliant on computers. This dependence needs formalization, and the theory of algebraic relations is one possibility. Under algebraic relations, "order" turns out to be of special interest in many applicational fields. Internationally renowned authors explain the theory and practice of order relations in such a way, that no specific mathematical skill is needed to understand the advantages of this algebraization. As the order relations are very general and simple, they can be used quite universally. For example, the structure of chemicals and their properties; evaluation of waste disposal sites, decision support for river management; and the way to measure biodiversity are examples of the broadness of the concept. This book is recommended to those, who are interested in the interface between sciences and management.