Niobium-3 Tin (Nb3Sn) is a very promising alternative material for SRF accelerator cavities. The material can achieve higher quality factors, higher temperature operation and potentially higher accelerating gradients (Eacc ˜ 96 MV/m) compared to conventional niobium. This material is formed by vaporizing Sn in a high temperature vacuum furnace and letting the Sn absorb into a Nb substrate to form a 2-3 µm Nb3Sn layer. Current Nb3Sn cavities produced at Cornell achieve Q ˜ 2 · 1010 at 4.2 K and Eacc = 17 MV/m. Here we present a summary of the current performance of Nb3Sn cavities at Cornell and recent progress in improving Eacc,. Content from this work may be used under the terms of the CC BY 3.0 licence (© 2018)