The purpose of the present study was to empirically test a newly developed theory of identity boundaries (Lile, 2013). In its initial theoretical construction, it is proposed that these boundaries are systematically related to identity style due to their similar, process-oriented nature. This study deviates from the original conceptualization of identity boundaries by hypothesizing that those with an informational identity style would have higher degrees of self–other differentiation than those with a normative identity style rather than vice-versa. College students (N=496, 69.4% female, 57.3% Caucasian) completed surveys of self–other differentiation and identity style. It was found that the informational identity style had the highest degrees of self–other differentiation, followed by the normative, and finally the diffuse-avoidant with significant differences occurring at all three levels, thus, supporting the hypotheses of the present study. Reasons for the deviation from Lile's theory are explored, implications of these findings are discussed, and new directions for this structural view of identity are proposed.