Firms specializing in submarine systems:

• DRG, formerly the David Ross Group - Technical and commercial consulting for international telecom.
• Information Gatekeepers Inc - Consulting, reports, and conferences.  Free daily e-news service.
• T. Soja & Associates - Also has a good list of cables and suppliers.
• Pioneer Consulting
• AXIOM - Submarine system telecom consultants starring Jean Devos.
• Telegeography - Great telecommunications reports and lots of free information at their web site.
• KIS-ORCA, formerly Kingfisher - The site contains charts in the area around the UK.

Other great telecom consultants:

• Ovum
• 451 Research