Non-leptonic B decays are our primary method to determine the angles  
of the unitarity triangle. Theoretical predictions for these decays  
are hampered by our inability to calculate required hadronic matrix  
elements from first principles. In this talk I will explain how we  
can use the effective theory SCET to perform an expansion in  
Lambda_QCD/mb to parameterize this hadronic physics in terms of a few  
unknown parameters,. These parameters can then be determined from  
experiment. After a brief review of SCET, I will compare the  
theoretical expectations with the recent data on B->pi pi, B->K pi  
and B-> K K decays.