Filled skutterudites are promising thermoelectric materials due to reduced thermal conductivity upon inserting a guest atom or 'rattler' into the CoSb(3) structure. By using an indium rattler dimensionless Figure of Merit (ZT) values >1 at 650 K have been reported. The conventional synthesis of these compounds typically takes several days (similar to 3 days) to obtain the final well-sintered material for property measurements. We report here a microwave-assisted synthesis method that reduces the initial calcination time from 2 days to 2 min. This route significantly reduces the time needed to produce materials suitable for property and device testing. (C) 2011 Elsevier Ltd. All rights reserved.