In the layered iron-based superconductor YFe2Ge2, a high Sommerfeld ratio of order 100 mJ/mol K^2 and a T^3/2 temperature dependence of the electrical resistivity at low temperature indicate strong electronic correlations and point towards an unconventional pairing state. Theoretical proposals for the superconducting state include s+- or triplet pair wavefunctions and there are striking structural and electronic similarities to some of the iron pnictide superconductors. Microscopic studies of the superconducting pairing state by muSR have been held back by the lack of high quality, bulk superconducting samples without ferromagnetic alien phases. We are now able to grow single crystals with a bulk Tc of about 1.1 K and RRR > 130. With this new generation of crystals, muSR measurements can produce a step advance in our understanding of the superconducting pairing state in YFe2Ge2.