Morteza Jafarzadeh - Faculty of Mathematical Sciences Ferdowsi University of Mashhad, Mashhad ۹۱۷۷۵, Iran
Hamed Reza Tareghian - Faculty of Mathematical Sciences Ferdowsi University of Mashhad, Mashhad ۹۱۷۷۵, Iran
Freydoon Rahbarnia - Faculty of Mathematical Sciences Ferdowsi University of Mashhad, Mashhad ۹۱۷۷۵, Iran
Reza Ghanbari - Faculty of Mathematical Sciences Ferdowsi University of Mashhad, Mashhad ۹۱۷۷۵, Iran

The project portfolio selection problem (PPSP) arises in economics and finance. Various formulations of the PPSP are proposed based mainly on integer programming techniques. The PPSP is known to be NP-hard. Therefore, standard optimizationtechniques (SOT) can only solve small instances of the problem in reasonable time. For larger and more complex instances such as when there is no precedence relation between the projects andthe profits yielded by the execution of some projects are allowed to be reinvested in new projects, SOT fail to provide solutions in acceptable time. For such problems, we propose a heuristic solutionprocedure based on branch and bound algorithm which provides good quality solutions in compatible running times. In order to demonstrate the applicability and efficacy of our proposed solutionprocedure, we generate and solve a number of large test problems.