While a large literature has established that migration experience among an individual's family and community networks tends to encourage migration, there is little research investigating the mechanism by which networks exert such effects. This paper aims to determine the relative importance of three potential benefits provided by networks: information on border crossing, information on jobs, and credit. We develop empirical tests of these effects based on a simple model that allows individuals to choose between migrating alone or with the help of a border smuggler. Using a dataset of undocumented Mexican migrants to the United States, we find that larger family networks encourage both migration and coyote use, consistent with the job information hypothesis. In contrast, community networks appear to provide crossing information. The finding that family networks have a smaller impact for asset holders indicates that some of the benefit the family network provides is a source of credit.