Implications of a small CP asymmetry in B -> psi K-S

New measurements of the CP asymmetry in B --> psiK(S), a(psi Ks), by the BA BAR and BELLE collaborations are consistent with the Standard Model predict ion for sin 2 beta. These measurements, however, leave open the possibility that a(psi Ks) is well below the Standard Model prediction. We identify de viations from the "reasonable ranges" of hadronic parameters that can lead to low values of sin 2 beta. New physics, mainly in B-0 - (B-0) over bar mi xing and/or K-0 - (K-0) over bar mixing, can explain low values of a(psi Ks ) in two ways: either by allowing for values of sin 2 beta below the Standa rd Model prediction or by modifying the relation between a(psi Ks) and sin 2 beta.