  Of the three angles that make up the CKM matrix, the least well known is
gamma. A precision measurement of this quantity is highly desirable as it forms
one of the arbitrary parameters in the Standard Model. Moreover, this is the
one angle of the CKM triangle that can be determined in channels that occur via
tree-level decays. While loop-level processes could have sensitivity to physics
beyond the standard model, tree level processes are expected to be unaltered.
Hence a measurement of gamma in tree level processes leads to a standard model
benchmark measurement against which other loop-driven measurements can be
compared. The measurements described here are the latest developments from LHCb
involving the decay B^+ --> D K^+, where the D meson is either a D^0 or a
anti-D^0 and the final state of the D meson is accessible from either flavour
state.
