  We review the currently available formalisms for radiative energy loss of a
high-momentum parton in a dense strongly interacting medium. The underlying
theoretical framework of the four commonly used formalisms is discussed and the
differences and commonalities between the formalisms are highlighted. A
quantitative comparison of the single gluon emission spectra as well as the
energy loss distributions is given for a model system consisting of a uniform
medium with a fixed length of L=2 fm and L=5 fm (the `Brick'). Sizable
quantitative differences are found. The largest differences can be attributed
to specific approximations that are made in the calculation of the radiation
spectrum.
