  The observed strong phase difference of 30^{o} between I=(3/2) and I=(1/2)
final states for the decay B to D Pi is analyzed in terms of rescattering like
D^{&#8727;}Pi to D Pi, etc. It is concluded that for the decay B^{o}to D^{+}
Pi^{-} the strong phase is only about 10^{o}. Implications for the
determination of sin(2 Beta + gamma) are discussed.
