What can we learn from a measurement of sin(2 beta + gamma)?

The constraints on the value of the Cabibbo-Kobayashi-Maskawa phase $\ensuremath{\gamma}$ that may be achieved by prospective measurements of $\mathrm{sin}2\ensuremath{\beta}$ and $\mathrm{sin}(2\ensuremath{\beta}+\ensuremath{\gamma})$ are discussed. Significant constraints require quite small errors, and may depend on assumptions about strong phases. The measurement of $\mathrm{sin}(2\ensuremath{\beta}+\ensuremath{\gamma})$ combined with other experiments could provide valuable limits on new physics in ${B}_{d}\ensuremath{-}$ mixing.