Weak Phases and CP Violation

Time-dependent CP asymmetries in $B^0$ decays from interference of $B^0$-$\bar B^0$ mixing and $b\to c\bar cs, u\bar ud, sq\bar q$, and direct asymmetries from interference of $b\to c\bar us$ and $b\to u\bar cs$ are studied, improving errors in the weak phases $\beta$ and $\gamma$ to $\pm 1^\circ$ and $\pm 7^\circ$, respectively. Two kinds of tests for New Physics are discussed: 1. Deviations of asymmetries in $b\to sq\bar q$ decays from $\sin 2\beta\sin\Delta mt$. 2. Violation of a sum rule for direct asymmetries in $B\to K\pi$.