The past research on radicalism is equivocal regarding the ways in which self-concept clarity shapes intentions to engage in radical behavior. Seeking to address the previous mixed findings in the literature, the present research examines how an individual's agency-communion orientation moderates the effect of self-concept clarity on behavioral intentions for radical groups. Specifically, we propose that agency-oriented individuals show greater intentions to participate in radical groups when they experience low (vs. high) self-concept clarity, whereas communion-oriented individuals show no significant differences in their intentions to participate in radical groups across levels of self-concept clarity. A 2 (agency-communion orientation: low vs. high) x 2 (self-concept clarity: low vs. high) experimental design was used to test the hypotheses. Using gender as a proxy variable for agency-communion orientation, Study 1 shows that agency-communion orientation moderates the effect of self-concept clarity on intentions to participate in radical groups. Using chronic individual differences in agency-communion orientation, Study 2 shows that psychological entitlement mediates the interactive effect of self-concept clarity and agency-communion orientation on behavioral intentions for radical groups. Taken together, these findings support the role of agency-communion orientation and self-concept clarity in radicalism.