Power generation planning seeks to achieve a reliable power system, economic efficiency, environmental sustainability, and social acceptability. Different alternatives of energy mixes that reflect emphasis on different strategic elements of energy policy are envisioned. For each alternative, a generation expansion pathway, comprised of different technologies introduced at different times along the planning period, is identified for each alternative considered. These pathways must be assessed in terms of multiple, sometimes conflicting, and often non-commensurate objectives. A power generation pathway can be evaluated using multiple criteria, each measured using a number of attributes. Sri Lanka, an island with no grid connection to neighboring countries and no fossil fuel reserves, currently needs to evaluate future power generation pathways. The objective of this study is to use a power capacity planning optimization model to determine details of a pathway for scheduling power plant additions for a set of alternatives and a demonstrate the use of multicriteria decision analysis method for identifying the "best" pathway for Sri Lanka. Different power generation pathways are developed and evaluated across multiple criteria and the preferences of multiple stakeholders. There is no clear winner among the pathways. A mix of renewable resources and fossil fuel constitutes an alternative that achieves energy security while satisfying multiple criteria associated with future power generation to a reasonable extent.