Measuring the impact of critical project success factors on project success in telecom companies Introduction: Project success is one of the ambiguous concepts in management of the projects. Since each person or group of people involved in a project has different needs and expectations from the same project, it is very common that they take the success of the project in their own way, according to their understanding (Cleland & Ireland, 2004). Research into project measurement deliverables and attention to key project management practices (time, cost, and quality) show that it is not possible to have one ubiquitous success criterion that fits all projects. The focus of project management activities differs from project to project based on a number of attributes such as project uniqueness, business, volume, complexity, customer preferences, and stakeholder interest. Therefore it is not sufficient to assume that time, costs and quality are the only success factors of a project but they must be explored and quantified with the overall definition of a series of multifaceted and unified project evaluation criteria (Ojiako et al., 2008) .The difference between criteria and factors is not clear to many people. The Cambridge Advanced Learner's Dictionary describes a criterion as "a standard by which something is judged, decided, or approached" while a factor is explained as "a fact or situation that influences the outcome of something". In this study I attempted to establish a relationship between project success factors and actual project success variables through literature and an empirical analysis adopted from the research of Andersen et al (2006). The focus will be on Pakistan's telecom sector. This is because in all… half of the paper… 24% worked as project managers, 62% project team members, 14% end users; 84% male, 16% female; 73% of projects were production or construction oriented, 12% research and development oriented, 15% decision support oriented; 32% work on large projects, 58% medium, 10% small. Analysis and Results The data is analyzed using SPSS version 16. Since all the questionnaires were self-administered, before publishing the questionnaire it was established that all respondents should be associated with activities related to project management and should be aware of the concept of project success project. The validity of the questionnaire was tested using Cronbach's alpha test (the results are reported in Table I). Appendix A contains the complete list of questions asked.