This paper shows how different "network" arguments about how protest spreads imply quite different underlying mechanisms that in turn produce different diffusion processes. There is considerable ambiguity about the relationships among networks, diffusion, and action cycles and the way these can be identified in empirical data. We thus both seek to unpack the "network" concept into different kinds of processes, and then show how these different network processes affect the diffusion processes we are studying. We sketch out some formal models to capture some of these distinctions. This paper extends recent work (Oliver and Myers forthcoming) that develops diffusion models of protest cycles, and focuses on discussing link between network concepts and diffusion concepts in understanding protest cycles. We conceive of social movements as diffuse action fields in which actions affect other actions and the action repertoires of the different actors coevolve through time and through interaction with each other. Movement activists and regimes engage in strategic interactions, each responding to the actions of the other. Different organizations within a movement respond to the actions of others, as successful tactical innovations and movement frames diffuse to new organizations. News media cover or fail to cover particular protests, and thus encourage or discourage future protests. Each of these processes effects the others, in a complex, multi-faceted set of interactions. Over time, the action set of each actor evolves in response to the actions of the others and, thus, the whole field is one large co-evolving environment in which the characteristics and actions of any actor is constrained and influenced by the characteristics and actions of all other actors in the environment.One central concern about understanding diffusion and networks in protest waves is that we do not actually have straightforward data about the underlying social networks or mobilization processes. Protest event data usually just contain records of the timing and location of events along with some (often incomplete) information about the participants in the event, their forms of action, their stated claims or other rhetoric (Kriesi, Koopmans, Duyvendak, and Giugni 1995;McAdam 1982;Olzak 1992;Tilly 1995). Rarely, if ever, will the data contain information on the social relationships or communication processes that were involved in organizing and mobilizing that event. Lacking this kind of data, we want to know whether different patterns of social organization will give rise to different patterns in protest event data, and how what we already about how protests get organized might influence our analysis of protest event data.After a brief review of the interplay between diffusion concepts and network effects, we develop some important distinctions among different processes often lumped together as