This study uses an affect theory of social exchange (Lawler 2001) to investigate how and when network structures generate "micro social orders." Micro social order entails recurrent interactions, emotional reactions, perceptions of a group, and affective sentiments. The core theoretical argument is that micro orders, involving behavioral, cognitive, and affective dimensions, develop and are stronger to the degree that (1) actors engage in highly joint tasks or activities and (2) these tasks generate a sense of shared responsibility for the interaction outcomes. A laboratory experiment varies different forms of social exchange - negotiated, reciprocal, generalized, and productive - within a network structure, and offers strong support for the core expectation that productive forms of exchange generate the strongest micro order. Conversely, generalized exchange generates the weakest order, with negotiated and reciprocal forms in between. In general, productive exchange bolsters more exchange behavior, more positive feelings, perceptions of cohesion at the network level, and affective attachments to the network as a social unit. This research has broad implications for the conditions under which task activity promotes micro social orders that involve strong person-to-group ties (as opposed to person-to-person ties) and affective sentiments regarding the social unit.