The interaction of multi-level atoms with several to many lasers simul
taneously is examined in two regimes, the 'short'' regime of resonant
atomic response to prescribed laser fields, and the ''long'' regime of
resonant pulse propagation in which several to many laser pulses pass
through an active medium composed of many-level atoms. Results obtain
ed with I. Bialynicki-Birula et al. in the short regime are reviewed,
and new results in the long regime are described.