Safety at Sea
Irish Coast Guard  
Royal National Lifeboat Institution  
Irish Water Safety  
Irish Marine Casualty Investigation Board Investigates accidents afloat in and around the Irish Republic
UK Marine Accident Investigation Branch Investigates accidents afloat in and around the UK including Northern Ireland

UK Maritime & Coastguard Agency

  Accident Reports
Yacht Bounder, English Channel, June 2007  
Yacht Hooligan, English Channel February 2007 Why Keels Fall Off - a very good article from Yachting Monthly (pdf file)
Yacht Legacy, Florida Keys, October 2005  
Yacht Moquini, South Africa September 2005  
Yacht Megawat, Irish Sea, May 2005 MAIB Accident Report (pdf file)
The Marine Accident Investigation Branch of the UK Department of Transportation is responsible for investigating maritime mishaps.  The MAIB regularly publishes Safety Digests which report on their investigations. 
Sailing Safety Digest
Powerboat Safety Digest

Tynemouth Tragedy
Two Lost Overboard
Tidal Near Misses
So Close to Home
Overtaking in Harbour
Lessons to Learn