IntroductionTo address the issue relating to the definition of the terms "Risk and Uncertainty" we should look at the general framework of project management as a business and at the management of changes that may occur during the project life cycle project due to the circumstances surrounding it, including political perceptions and value management that are vital in making decisions. However, there have been numerous researches interested in entering the field of risk management, where it has influenced some areas such as “crime, social work, health, regulation and organization” (Zinn 2009). However, APM (2006) has defined project management as “the process by which projects are defined, planned, monitored, controlled and delivered such that agreed benefits are realised. Projects are one-off, transitory efforts undertaken to achieve a desired outcome. Projects bring about change and project management is recognized as the most efficient way to manage that change.” All projects are unique and complex in terms of time, budget, circumstances, quality, performance, and geographic location and culture, furthermore, they are constrained with limited resources, in addition to estimates made by people based on previous experiences or some probabilities (APM 2006). Not to forget the participation of stakeholders in the multiplicity of outcomes that result from the accumulation of serious events or the lack of reliability and uncertainty in the project as a whole (APM 2006). APM (2006) shows that “project risk management must be integrated into project management and should be used throughout the project life cycle”. Therefore, monitoring and controlling the multiple tasks of...... half of the paper ......g uncertainty in projects – a new perspective,International Journal of Project Management, 26(1), 73-79, Elsevier . Slovic P. (1999). Trust, emotion, sex, politics, and science: Battlefield analysis for risk assessment, 19(4), Society for Risk Analysis. Smith NJ eds. (2003). Evaluation, risk and uncertainty. London: Thomas Telford.Ward, S., Chapman, C. (2003). Transforming project risk management into project uncertainty management, International Journal of Project Management, (21), 97-105, Elsevier.Zinn, J. O. (2009). The sociology of risk and uncertainty: current status and prospects. In: Lockie, S. et al. (ed.): The Future of Sociology (Proceedings of the TASA 2009 Conference). The Australian Sociological Association [online] Available from: http://www.tasa.org.au/conferences/conferencepapers09/papers/Zinn,%20Jens.pdf [accessed 5 February 2012].