Space is important for any work of art. Positive, negative, and what Susan calls "invisible" space, all contribute to the three dimensional nature of a design. Invisible space is the space between the layers of the different elements in your design and it is key to creating depth in an arrangement. You can not see this space because it is obscured by the element in front of it, but without it, the whole arrangement would appear flat and two dimensional.
It is always a pleasure to see a master at work. Susan Cano gave us a lot to think about at this April meeting of Ikebana International; using space and line and focal points to create depth, movement and drama. It was a mind blowing demonstration considering she created seven arrangements in under an hour!