Working with Joss is amazing. He's just such a creative force and he really has a vision. It's wonderful when you're working with someone who's created an entire world, because then you're really clear about what world you're stepping into and how to flesh out your part of it.
He was always so hands-on, involved in every wardrobe choice, all the visuals, obviously writing, producing and directing episodes - and it really shows. Often when you're working on a series it starts out one way and then it gets delegated to somebody else. Buffy has never had that feeling because there's always been that clarity.