  We give a pedagogical review to alternative, first quantised approaches to
calculating graviton scattering amplitudes, giving an introduction to string
inspired approaches and presenting more recent work based on the worldline
formalism of quantum field theory that is motivated by these historic results.
We describe how these first quantised techniques can greatly simplify the
determination of such amplitudes, in particular reducing the number of
Feynman-like diagrams that enter the computation and leading to compact
results.
