Time slippage frequently occurs in construction projects throughout the world and Pakistan is no exception. This phenomenon is especially significant in public sector where most of the projects complete beyond their target dates. Though there are numerous factors that cause time slippage, the emphasis of this study is to identify those for which the owners are responsible. Lack of knowledge and poor appreciation of proper planning for different phases of construction projects and its impact on cost and time is a dilemma for owners. This research is based upon three case studies of public sector projects and aims to identify different factors that cause delays in public sector construction projects in order to help different stakeholders find the causes of delays due to the owners’ action or inaction. This research also looks into cost overruns resulting from delays, with the aim at educate the owners about their responsibilities towards different phases of construction projects and devise measures to mitigate different types of claims, which may arise because of these delays. The most common delay factors, such as, inadequate design details at the start of the project; major changes in design; late issuance of construction drawings; inadequate funding and delay in issuance of NOC’s/approvals associated with government agencies, have been identified to help owners in planning the projects in an efficient and effective manner. The results of this study are expected to improve the contribution of owners in overall project management. Results will also be helpful for consultants, designers and contractors in anticipating the problems during execution of the projects.