In this paper, ways of improving planning, execution and management of complex engineering projects using design structure matrix (DSM) methods: path searching, powers of the adjacency matrix, and reachability matrix are presented. This is done by identifying loops or circuits in the project. The application of the DSM methods to minimize loops or circuits is discussed. As a case study, these methods are implemented to reduce design iterations or rework in a complex engineering project. By applying the DSM methods, the project duration can be minimized and hence the total cost of the project is reduced significantly.