The document discusses using social norms marketing to de-normalize smoking and reduce tobacco use. It notes that people's behavior is strongly influenced by perceived norms (what they think others do), not just actual norms. Effective interventions include both changing individual behaviors and social/physical environments to make smoking less acceptable and accessible. The document proposes using local data to show communities accurate norms of low smoking and smoke-free homes/cars to reshape perceptions and social norms around tobacco use.