The EUMETNET Council accepted at its 26th meeting in October 2005 the creation of the Working Group on Instrumentation (WG-INS) with the objective to exchange information on test reports, test results, future national test campaigns, tender procedures and requests for extra information. At its 11th Meeting in November 2005, PB-OBS discussed the technical organisation of this group and decided to draft Terms of Reference for the Working Group. These TOR were accepted at the 12th Meeting of PB-OBS in March 2006 and Jochen Dibbern, DWD was nominated as the Co-ordinator to organise the Kick Off Meeting for the Working Group.