The document discusses optimization techniques for telecommunications network design. It explains that telecommunications networks have become increasingly complex due to factors like heterogeneous services, mobility, and deregulation. As a result, network design problems are also more complex, with many possible design solutions. The chapter provides an overview of how optimization models and algorithms can be applied to problems in telecommunications network design, such as topology design, dimensioning, configuration, routing, and resource allocation. Many of these problems can be formulated as mixed-integer linear programs.