In order to improve their competitive positions, organizations have always been looking for tools to improve their business strategies and to use the resources at their disposal effectively and efficiently to achieve their objectives. Unfortunately, to date, most of the proposed tools do not adequately address this need when managing a project portfolio when dealing with project selection and critical resource allocation. The objective of this paper is to propose a heuristic based on the deterministic model to show how senior management can easily control the number of selected projects while verifying the quantity of scarce resources available in order to avoid conflicts and better manage prioritization issues between different projects.