The article analyses the participation of young people in emerging social movements, focusing on the experience of the Italian Non Una Di Meno (NUDM) movement combatting male violence against women. Challenging scholarly assumptions of growing youth apathy in democracies, the analysis reveals high levels of participation on the part of the younger population engaged in gender-related struggles. Hit by both conservative and austerity policies associated with the economic and political crisis, feminist and LGBTQI (lesbian, gay, bisexual, transgender, queer, and intersexual) Millennials reacted by increasing their involvement in contentious politics. In the protest arena, they have crossed paths with older generations, activating processes of exchange, but also intergenerational tensions. Based on original qualitative data from ten semi-structured interviews with movement activists in Florence and Bologna, this piece of research sheds light on the role of young people in the birth and evolution of NUDM, and the relationship between different generations of activists within this movement. More specifically, it explains continuities and discontinuities between veterans and younger activists’ sources of theoretical inspirations, organizational models and mobilization resources, strategic priorities and action repertoires. Millennials embrace intersectional feminism and queer theory; opt for grassroots, horizontal organizing; adopt a conflictual attitude towards the state, and dialogical, introspective dynamics within the movement. Intergenerational disagreements especially relate to sex work, and surrogate motherhood.