This book is a collection of articles studying various Steiner tree prob- lems with applications in industries, such as the design of electronic cir- cuits, computer networking, telecommunication, and perfect phylogeny. The Steiner tree problem was initiated in the Euclidean plane. Given a set of points in the Euclidean plane, the shortest network interconnect- ing the points in the set is called the Steiner minimum tree. The Steiner minimum tree...