Before revision:  I  show that intention-to-treat parameters aggregate a large number of direct and spillover effects for different compliance types, and hence they may not have a clear causal interpretation.
After revision:  I characterize the population compliance types in a setting in which spillovers can occur on both treatment take-up and outcomes, and provide conditions for identification of the marginal distribution of these compliance types. I show that intention-to-treat parameters aggregate a large number of direct and spillover effects for different compliance types, and hence they may not have a clear causal interpretation.