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International Maritime Organization Navigation and Communications Legacy Documents

International Maritime Organization (IMO) Resolutions, Circulars and other documents can generally be found on the IMO website or in its web accounts portal.   However, older IMO communications and navigation documents not generally available on their website have been preserved and are available here.

Collision Regulation (COLREG) Circulars


Communications COM


Communications and Search & Rescue (COMSAR)
Subcommittee Reports


Safety of Navigation (SN)

For additional information about the IMO, visit’s IMO page.

Mailing Address:

International Maritime Organization
4 Albert Embankment
London SE1 7SR UK

Telephone, fax, and email:

tel: +44 171 735-7611
fax: 587-3210 (general enquiries), 587-3241 (publication sales).
email general equiries:
email publication sales:

IMO Website: