The construction industry plays significant role in the economy of developing countries, where Lebanon is one of. However, the performance industry remains under critique. Many projects encounter considerable time and cost overruns, fail to realize their intended benefit or even totally terminated and abandoned before or after their completion. As the construction project goes through many phases, the success of each phase will affect the success of the project. Thus, the “Project Success” notion is becoming a priority in the Lebanese construction sector. This paper describes a study of the time, cost and quality management trilogy impact on the success of the local Lebanese construction projects. It shows the importance of each factor and its role in the attainment of client objectives. A Questionnaire survey, supported by “face to face” interviews, elicit the attitude of owners (developers), consultants, and contractors towards the factors affecting each parameter is done. Conclusion and remarks for future construction quality system rating will follow.