He is a member of Communia Network, and of the Italian section of the Fourth International. He has written several books: Porto Alegre, capitale dei movimenti (manifestolibri, 2002), La rifondazione mancata (Edizioni Alegre, 2009), Altre Sanguisughe (Aliberti, 2011), C’era una volta la Fiat (Aliberti, 2012), Mutualismo, ritorno al futuro per la sinistra (Alegre, 2018).