  We address a number of theoretical and phenomenological issues in two-body
charmless non-leptonic B decays in the context of a factorization model. A
classification of the exclusive decays involving tree and penguin amplitudes is
reviewed. The role of QCD anomaly in exclusive decays involving an $\eta$ or
$\eta'$ is elucidated and comparison is made with the existing data. We argue
that the factorization approach accounts for most of the observed two-body B
decays.
