The present document is intended to provide guidance on the use the ETSI EN 301 489 series [i.2] of harmonised EMC standards produced by ETSI ERM. Specifically this guidance covers selection of which part that is to be selected for use in conjunction with ETSI EN 301 489-1 [i.2] to provide the necessary requirements to enable the user to demonstrate compliance with article 3.1(b) of the Directive 1999/5/EC [i.1] (RTTE Directive). The aim of this is to increase consistency of application. In addition the present document also details the differences between the individual versions of each part of the ETSI EN 301 489 series [i.2] to assist the reader in reaching a decision on the impact of the different versions on their particular product. In the interest of maintaining the document as up to date as possible the present document starts with those versions of the ETSI EN 301 489 series [i.2] cited in the Official Journal of the European Union (OJEU) on the 29th December 2010.