Sustainability is a field of growing interest in Project Management (PM). Literature on Sustainability in PM is abundant at a theoretical level; however, it is necessary to explore hands-on approaches for designing models and practices. The purpose of this study is to introduce management systems as a practical tool for Sustainability in PM. Management system certifications are used as an indicator of the implementation of Sustainability practices, and thus, the impact of Sustainability on the success of projects is analyzed. The methodology for this study includes the analysis of the correspondence between Sustainability and five recognized management system standards (ISO 9001, ISO 14001, ISO 50001, UNE 166002 and OHSAS 18001) and experimental research based on data delivered by CDTI (Center for Industrial Technological Development) including relevant and objective information about R&D&I Projects in the energy sector. This study analyzes the impact of four variables (duration, budget, year of funding and certifications to management systems) on the success of the project. The conclusion is the significant positive impact of having management system certifications on the success of company projects analyzed in the Spanish energy sector, which may be of interest to PM practitioners in order to consider Sustainability as a factor for success.