Decreasing errors in experimental data obtained from colliders like the LHC
makes it necessary to invoke higher and higher orders in theory predictions.
A crucial part of the NNLO QCD predictions is the handling of the double real radiation phase-space and the cancellation of IR divergences with other contributions. I present a new phase-space parameterization for the sector-improved residue subtraction scheme as well as a new method for the evaluation of the corrections needed to employ the four-dimensional 't Hooft - Veltman scheme. Furthermore novel applications of the subtraction scheme are discussed.