In recent years, many companies around the world have adopted different forms of quality systems, such as ISO-based quality systems, or BS-based quality systems. It has been perceived that a quality-based company provides higher quality services and products in comparison with non quality-based companies. As a result, quality-based companies have become reputable and attract more customers. In projects construction field, quality has become very essential for both contractors and owners. Contractors tend to provide high quality deliverables to satisfy their clients, and to remain successful in this turbulent business field, while owners want to receive high quality end-products and services, and to ensure that their deliverables matching contractual quality requirements. Therefore owners (whether operating companies or government sectors) have developed different means to measure quality in their projects, such as hiring professional consultants who cooperate with owner’s project team. If owners have developed reliable quality management system (QMS) and their staffs are experienced and competent with relevant technical and project management knowledge, then the result will be outstanding. This study is aimed to design, implement, and examine a QMS in Garri4 power plant project, NEC, Sudan – which has already completed 60% of its activities on the time of QMS implementation. The outcomes of this implementation are intended to be used for future NEC projects. The outlines of the QMS have been prepared from the PMBOK guide, which has been published by PMI (Project Management Institute, USA) as a guide for project management knowledge and practices. In addition to that, the detailed QMS work frame has been designed on the guidance of relevant literature review and joint meetings with NEC project team. The required data before and after the QMS implementation gathered using questionnaires, and a Matrix model has been used to measure QMS objectives and requirements effectiveness based on the collected data. The final results indicate success on meeting QMS prescribed objectives, while meeting QMS requirements during QMS implementation failed. An extensive analysis based on real observations during QMS implementation and these results has been carried in order to determine driven factors. Finally, a conclusion and recommendations have been drawn.