NYC's buses have their own flaws, but they demonstrate many of the necessary conditions for success: dedicated bus lanes, split-service (local and express on the same route, with corresponding bus sizes), and multimodal connections (light rail, streetcars, subways). This is all in contrast to how many bus networks in the US operate: they pick you up on the side of the highway, drive with the rest of traffic, and drop you off on either the highway or in a bus depot in the middle of nowhere.