Lise Jans  is an Associate Professor within the Environmental Psychology group at the University of Groningen. Her work contributes to understanding group dynamics and their impact on individuals and communities. Her research focuses on the (trans)formation of group identities, and their influence on individual and collective behaviors. During her visit, she have the conference «Can Small-Scale Bottom-Up Actions Motivate Large-Scale Sustainble Change?», in which she proposed that strong pro-environmental social identities can be formed from the bottom-up, induced out of individual contributions and interactions of group members. She presented research examining the conditions under which various pro-environmental initiatives in cities, schools and organizations, enable the formation of pro-environmental social identities, and behaviors in line with this identity. Together, these studies provide insights into the importance of visible small-scale bottom-up actions in motivating large-scale social sustainable change.