Entrepreneurial employees are crucial to successful CE and for developing radical innovations. Entrepreneurial behavior means dealing with situations of uncertainty, which arise especially in the fuzzy front-end of innovation. Effectuation is a behavioral logic to deal with uncertainty. This study applies effectuation theory to the fuzzy-front end, and derives individual level and organizational antecedents to effectual and causal behaviors from the literature on entrepreneurial personality traits and CE organization. Using cross-sectional survey data from 56 corporate employees, we show that a proactiveness, tenacity, and internal locus of control influence specific behaviors, as do work discretion, time availability, and management support. This study contributes to CE and innovation literature by deepening the understanding of the effects of traits and organization on employee behavior, and advances effectuation theory by suggesting individual and environmental antecedents to effectual behavior