robert bazell with march on a group that s taking the struggle to the streets and beyond that. reporter: today demonstration by the militant group, act up. it has increasing influence on aids policies. the weekly meetings attract hundreds. and it counts 10,000 members nationwide. mostly young, mostly gay. let s do a big demonstration there and keep it there. reporter: the atmosphere at the meetings and group s headquarters characterized by enthusiasm and belligerance toward established institutions. playwright larry kramer started act up to accelerate the aids drug approval process. what right doesรง the fda an nih have the right to tell a dying person what to do with his or her body. reporter: act up s tactics often offend.