i'm joined by barry hooper, primary orchestraitor of a number of the key ordinances, as well as advancementf the ordinance itself. san francisco as we know as a history of being both remarkably cool and impressively green. under the leadership of director rafael and the commission, the city has been widely emulated and a thought in best practices leader nationally and internationally. until relatively recently, there was an exception to this environmental leadership legacy. the same could not be said of greener living roofs. while we had outstanding examples about the city and a remarkable one in process and transbay, we had no will policies or programs in place specific to their implementation. to begin to address that deficiency, the planning department conspired with the p.u.c. and s.f.c.-s.f.e. to lure the preeminent international green roofs conference to the city. we hosted the cities alive conference in 2013 which catalyzed our bringing together the trades, agencies and other green experts and fanatics. well, actually, we're all fanatics. in anticipation of the conference, spur conve