The two-week holiday in the islands of Grenada and Carriacou, valued at £6900, will be free to enter to all visitors to the show, which takes place at ExCeL on the weekend of 26/27 March.
The islands boast well-populated coral reefs, wrecks, and diving suitable for all ability levels. Signature dives include the huge liner Bianca C, one of the world's most acclaimed wreck dive sites. Like other Grenada reefs, both natural and artificial, it hosts abundant marine life, including barracuda, eels, rays and sharks.
The lucky winner and a chosen companion will have return flights from London to Grenada, courtesy of British Airways. Accommodation in Grenada will be at the Flamboyant Hotel & Villas and Grenadian By Rex hotels, and there will be 12 dives with Dive Grenada and Devotion2Ocean. In the neighbouring island of Carriacou, accommodation will be shared between Ade's Dream and Carriacou Grand View Hotel, and there will be another 12 dives, with Carriacou Silver Diving and Lumbadive.
The holiday prize draw will be just one of many exceptional visitor attractions at LIDS 2011 - the 10th-anniversary dive show at ExCeL.
Already lined up for the speaker programme - which is also free to all show visitors - are two of Britain's foremost - and most active - divers.
Following the completion of filming for his third Great Escapes TV series, Monty Halls will be at ExCeL to talk about his experiences on location off the West Coast of Ireland, which included encounters with Atlantic whales and dolphins. And the irrepressible Paul Rose will also be there, describing his second BBC Oceans series - this time majoring on diving around the British Isles.
Other marine-life experts at the show will be two based in southern Africa. Making serious waves in the world of big animals, as indicated by their nicknames, are "Queen of the Mantas" Andrea Marshall, and "Shark Warrior" Lesley Rochat.
Meanwhile, heading up the technical side of the speaker programme - both at LIDS and at the TEK 2011 Advanced Diving Conference which will run alongside the show - will be one of the world's most experienced divers in the field.
Not only did John Garvin co-write the script for "Sanctum", James Cameron's 3D follow-up to "Avatar", but he was also diving coordinator and acted in the film. LIDS organisers are therefore delighted that he has agreed to be at the show to talk about the making of this eagerly-awaited movie.
Other features at LIDS 2011 will include the British Isles Experience, the Red Sea Zone, the Caribbean Village and the new Asia-Pacific Showcase. There will also be two dive pools - Beginner and Technical - and the New Dive Gear Showcase, which this time will have a technical twist.
The show will also exclusively feature the NoTanx Freedive Simulator, which, offering visitors the chance to test their breath-hold skills, proved a big hit at DIVE 2010.
LIDS organisers have also announced the launch of a new Photo Zone in the show hall. Details of this are currently being finalised but it will, for the first time, include U/W photo courses available free to a dive-show audience.
* See what to expect at the dive shows on this video.