Grid reliability and resilience are foundational to meeting electricity needs and have significant economic and societal impacts. 1 Energy efficiency can help meet grid reliability objectives and improve resilience, but metrics and methods used today may not fully recognize these benefits. This technical brief-aimed at state regulators and policy makers, utilities, and stakeholders-explains how existing planning processes for bulk power and distribution systems capture the impact of energy efficiency on power system reliability and resilience. We identify limitations in using existing reliability and resilience metrics to quantify efficiency and other distributed energy resource (DER) benefits. The brief concludes with opportunities for enhancing planning practices to better capture the reliability and resilience value of energy efficiency and identifies research needs.4 See https://emp.lbl.gov/projects/what-it-costs-save-energy and https://emp.lbl.gov/projects/projections-spending. 5 We do not discuss utility distribution system efficiency measures-conservation voltage reduction or volt-VAR optimization. We also do not explore in detail reliability and resilience benefits of DERs other than efficiency, such as demand response, battery storage, microgrids, and managed charging of electric vehicles. For additional information on the reliability and resilience benefits of these DERs, see Rickerson et al. 2019, Rickerson and Zitelman forthcoming,