This article argues that an approach to unbounded harmony that enforces restrictions only over adjacent elements undergenerates for patterns with nonlocal trigger-target relations. Such patterns may occur even in cases where assimilation propagates locally, as found in Baiyina Oroqen and Mọ̀bà Yorùbá. However, a harmony im(perative that is not restricted to adjacent elements is capable of producing these systems, in which a trigger may be related to both adjacent and nonadjacent targets. The appropriate one-to-many relational structure is compatible with Optimality Theory, where well-formedness is evaluated over the entire candidate at once, but it is not consistent with a local iterative spreading rule or an approach using a local spreading constraint, lacking additional constraints on nonlocal dependencies. This study thus identifies a previously unrecognized advantage of analyzing harmony within Optimality Theory, and it signals the necessity for any theory of harmony to handle nonlocal trigger-target relations.