Risk management is an essential and integral part of project management in the oil and gas industry. For an oil and gas infrastructure project, risk management can be carried out effectively by investigating and identifying the sources of risks associated with each activity of the project. These risks can be assessed or measured in terms of likelihood and impact. Because of the exploration basis of the oil and gas industry, a different and diverse set of risk concerns will be involved. So, as risks are assessed for managerial processes, technical and exploration risks must also be assessed. Risk and estimation of reserves constitute a major portion of project risk analysis in the oil and gas industry. The major activities in oil and gas risk analysis consist of feasibility studies, design, transportation, utility, survey works, construction, permanent structure works, mechanical and electrical installations, maintenance, and so on. This chapter addresses only selected topics from the list.