Collaboration is often touted as the ideal interorganizational relationship (IOR) to tackle many challenging social problems; however, collaboration is just one of many types of IORs that public managers can undertake. This article presents public managers’ decisions to cooperate, coordinate, or collaborate with program partners as strategic responses of avoiding, compromising, or acquiescing, respectively. We argue that perceptions of coercive, normative, and mimetic pressures influence the likelihood to undertake different IORs; specifically, as managers experience combined isomorphic pressures, they are more likely to acquiesce and collaborate with program partners. Findings from our qualitative study of federal and state preschool programs in Virginia, USA reveal that as managers perceive additional pressures they are more likely to pursue more involved IORs. Unexpectedly, we find that cooperators perceive few isomorphic pressures, and we also find that perceived deterrent isomorphic pressures distinguish coordinators from collaborators. These findings offer insight about how organizational field pressures can affect strategic IOR responses.