Educational performance based on the learning outcomes of formal schooling in a future knowledge society could be significantly different from that of today. This study investigates the possibilities of developing an educational performance indicator for new-millennium learners (NMLs). The researchers conducted literature reviews, a meeting of experts, pilot studies, and a nationwide survey to define and refine a concept of educational performance required by a knowledge society. The study identified cognitive, affective, and sociocultural domains as core constructs of the indicator. We conducted exploratory and confirmatory factor analysis to validate the indicator. We have identified three domains with four factors in each have to measure the educational performance of NMLs. Information management, knowledge construction, knowledge utilization, and problem-solving abilities are four factors in the cognitive domain. The affective domain consists of self-identity, self-value, self-directedness, and self-accountability factors. Finally, the sociocultural domain includes social membership, social receptivity, socialization, and social fulfillment factors. (Contains 12 tables.)