During the 1990’s, the former European Telecommunications Office (ETO) undertook several studies for the European Committee for Telecommunications Regulatory Affairs (ECTRA) of the means of improving the efficiency and effectiveness of numbering, naming and addressing from a regulatory point of view. This work, some of which was initiated at the request of the European Commission, was in response to the recognition that numbering is a key issue in a competitive environment to ensure easy access to networks and services. In parallel with these studies, the ETO also undertook several studies with regard to the establishment of a European Telephony Numbering Space (ETNS).

The reports of the studies listed below are available for download.

ECTRA Report 48264	Non-discriminatory access to numbering resources	July 1996
ECTRA Report 48267	Numbering related to the topic of user-friendliness	October 1996
ECTRA Report 48341	Carrier selection	July 1997
ECTRA Report 48378	Review of national numbering schemes on their openness to competition	October 1997
ECTRA Report 48379	Harmonised national numbering conventions	October 1997
ECTRA Report 48263	Numbering related to personal communications services (PCS) in Europe	November 1997
ECTRA Report 48374-75-76	Management, routeing & portability aspects of the European Telephony Numbering Space (ETNS)	June 1998
ECTRA Report 48380	Harmonisation of short codes in Europe	September 1998
ECTRA Report 48461	ETNS field trial 1: scope, architecture, work plan & business plan	January 1999
ECTRA Report 48502	Project management, administration & registrar functions for the ETNS field trial, phase 2	September 1999
ECTRA Report 48377	The numbering requirements of corporate telecommunication networks (CNs) & their impact on public network numbering	November 1999
ECTRA Report 48381	A long term strategic plan for the numbering & addressing of telecommunications services in Europe	November 1999
ECTRA Report 48465	Harmonised national conventions for naming & addressing	December 1999
ECTRA Report Apr 00	Number portability for mobile networks	February 2000
ECTRA Report Nov 00	The effect of number portability on national number administration & management	November 2000