This paper analyses the legislative cosponsorship in the Chilean Chamber of Deputies over the 2010-2014 and 2014-2018 legislative periods. Specifically, using a Social Network Analysis (SNA), the representatives' bills coauthorship is studied in order to identify and compare legislative work strategies. Exploring the cosponsorship allows us to observe and analyse the actors' behaviour and the party and coalition strategies. The findings show the relevance and centrality of certain actors in the cosponsorship, as well as the logic of collective work, which break the Chamber's coalitions up and modify them.