CP Violation and Quark Mixing

Measurements of CP asymmetries in B decays will soon be made at $B$ factories and hadron machines. In light of this, we review and update the profile of the CKM unitarity triangle and the resulting CP asymmetries in B decays. This is done both in the standard model and in several variants of the minimal supersymmetric standard model (MSSM), which are characterized by a single phase in the quark flavour mixing matrix. After imposing present constraints on the parameters of these models, the predicted ranges of $\sin 2 \beta$ in the standard model and in the MSSM are found to be similar. However, these theories may be distinguished by future precise measurements of the other two CP-violating phases $\alpha$ and $\gamma$.