This document specifies requirements for, and gives guidance on, the application of life cycle costing for the development activities and operations associated with drilling, exploitation, processing and transport of petroleum, petrochemical and natural gas resources. This document covers facilities and associated activities within different business categories (upstream, midstream, downstream and petrochemical). The life cycle costing process as described in this document is applicable when making decisions between competing options that are differentiated by cost and/or economic value implications. This document is not concerned with decision making related to the economic performance of individual options or options differentiated by factors other than cost or economic value. Guidance is provided on the management methodology and application of life cycle costing in support of decision making across life cycle phases. The extent of planning and management depends on the magnitude of the costs involved, the potential value that can be created and the life cycle phase. It also provides the means of identifying cost drivers and provides a cost-control framework for these cost drivers, allowing effective cost control and optimization over the entire life of an asset.