  Splitting amplitudes govern the behavior of scattering amplitudes at the
momenta of external legs become collinear. In this talk we outline the
calculation of two-loop splitting amplitudes via the unitarity sewing method.
This method retains the simple factorization properties of light-cone gauge,
but avoids the need for prescriptions such as the principal value or
Mandelstam-Leibbrandt ones. The encountered loop momentum integrals are then
evaluated using integration-by-parts and Lorentz invariance identities. We
outline a variety of applications for these splitting amplitudes.
