  Renormalization ideas can profitably be exploited in conjunction with the
superposition principle of boundary conditions in the description of model
independent and universal scaling features of the singular and long range Van
der Waals force between neutral atoms. The dominance of the leading power law
is highlighted both in the scattering as well as in the bound state problem.
The role of off-shell two-body unitarity and causality within the Effective
Field Theory framework on the light of universality and scaling at low energies
is analyzed.
