I've always thought that Leibniz's monadology offers comfort during parallel session conferences. Assuring us that each monad reflects the whole, although from its particular point of view, Leibniz makes the sanguine case that one can make sense of things even if one's viewpoint is sadly singular. In the mad rush from one paper session to the next, knowing that at best one gets to hear a third of what is being said, it helps to invoke a bit of Leibnizian optimism. And indeed, Dublin seemed like a best possible world during the three days of the Defining Space conference taking place in October 2007. Generously hosted and meticulously organised, the University College Dublin-led event succeeded not only in attracting more than eighty papers that contributed to elucidate the concept of space in relation to architecture, art, and the city, but also in creating an atmosphere of conviviality and intellectual generosity which gave the event an unusual sense of sharing.