Delays are one of the biggest problems in construction projects in developing countries, as cause negative effects on the projects. Delays can be minimized only when their causes are identified. This paper aims to identify effective methods of minimizing delay in construction projects. The literature related the field of causes and effects of delay and methods for minimizing construction delay has been reviewed over the last decade. This paper highlighted methodology to reduce construction delays from consultant and contractor viewpoints. The perspective of contractors and consultants has been analysed to rank the methods of minimizing construction delays based on their Relative Importance Index (RII). The most effective methods of minimizing delay in construction projects were: adequate funding throughout the project, competent project manager, awarding bids to the right designer/contractor, complete and proper design at the right time, availability of resources, clear objective and scope, and the use of experienced subcontractors and suppliers. The result can be used as a guideline to successfully handling construction projects in Iran as well as other developing countries.