Leadership has been a topic of much interest in the analysis of social movements. Drawing from qualitative fieldwork, this article analyses the leadership that was developed by Ester Quintana, who was the last victim to be injured by a rubber bullet during a demonstration in Barcelona (Spain). Together with her friends and other people, Quintana created the "Ojo con tu ojo" movement (Watch out for your eye). Specifically, the article explores the relevance of Quintana's prior experiences in participatory and dialogic movements and identifies the way that she transferred this knowledge to "Ojo con tu ojo" as the key to the success of the movement. In only 12 months, "Ojo con tu ojo" achieved something that other similar social movements in Spain had not achieved in the past: a legislation change that bans the use of rubber bullets by the police.