  The aim of the Working Group on Single Beam Behaviour was to concentrate on
the items limiting the achievement of high luminosity. Some are related to high
current and short bunch distance, as electron cloud instability (ECI), the
others to the lattice design, as Dynamic Aperture (DA), wigglers, Interaction
Region (IR) design, lifetime and background. These arguments have been
discussed to explore the feasibility of a very high luminosity Phi-factory.
