  A new theoretical method is introduced to study coherent electron transport
in an interacting multilevel quantum dot. The method yields the correct
behavior both in the limit of weak and strong coupling to the leads, giving a
unified description of Coulomb blockade and the Kondo effect. Results for the
density of states and the temperature dependent conductance for a two- level
dot are presented. The relevance of these results in connection to recent
experiments on the Kondo effect in semiconducting quantum dots is discussed.
