Studies have hypothesized conflicting results regarding the effect of actors' interpersonal attachment on commitment to the encompassing large group. The cohesion approach hypothesizes that interpersonal attachment among actors will enhance group cohesiveness, which produces more commitment to the large group. In contrast, the subgroup approach predicts that interpersonal attachment among actors will contribute more to subgroup fragmentation which sets up barriers to actors' commitment to the large group. We derive hypotheses from these opposing approaches and test the hypotheses over a sample of 1621 employees drawn from 62 work organizations in Korea. The empirical tests indicate the following: (1) Interpersonal attachment among employees in local work units is shown to have a positive effect on commitment to the work organization encompassing the work units. (2) Interpersonal attachment between dissimilar positions in the same work units is shown to have a more positive effect on commitment than that between similar positions. Implications of these findings on the two theories are discussed.