Artificial Intelligence is increasingly woven into critical societal infrastructures, from healthcare and transportation to education and public services. Designing such socio-technical systems responsibly demands more than technical expertise—it requires integrating ethical, legal, social, and organisational perspectives from the outset. This 90-minute fishbowl panel explores how intersectoral collaboration between academia, industry, civil society, and/or governments can drive responsible and innovative AI systems design through enhanced Requirements Engineering practices. It brings together voices from across sectors to discuss concrete strategies, examples, and lessons learned when aiming at intersectoral research and innovation in RE, with a specific focus on real-world socio-AI concerns. This panel session invites dynamic, participatory dialogue in a fishbowl format, enabling rotating participants from the audience to engage directly with the panellists. The goal is to uncover practical insights and foster new collaborations that go beyond disciplinary or sectoral silos.