Planet Cruise, the brainchild of former P&O sales manager Jenny West, began as a humble home venture in February 2004, but has since ballooned in size to become one of the UK's leading cruise specialists.

The firm arranges luxury holidays on board dozens of 'floating resorts' around the world, and is now preparing its first cruise fair at Portsmouth's Royal Marines Museum this Sunday.

Despite chilly economic waters, buisiness remains buoyant for the firm, which has now announced a turnover of £12m for the year ending August 2008 – a leap of 300 per cent on the previous 12 months.

But the firm, which now employs 14 staff, and is nestled in a thoroughly modern office building in the town, is still not satisfied. It has ambitions to grow turnover to a colossal £24m in the coming year, and is currently recruiting another six employees.

Founder and customer services director Jenny West said she was filled with pride at the achievements – and was raring to show off what the firm has to offer this weekend.

She said: 'I ran it for the first year with absolutely zero in start-up capital.

'I started it at home, converted the garage, and then the next thing you know, one booking becomes two bookings, then four, then eight, and it just spiralled from there.

'Now this is our first cruise show, and we're very excited about it. I do feel incredibly proud in the business. The feeling comes from people who say "that was the best holiday we've ever had. Where are we going to go next?"

'We are one of just a few who specialise in this. Not just anyone can sell cruises. Every single ship has its own personality, and you have to know it inside out.'

More than 20 large-scale cruise ships are currently in production around the world – including the world's largest-ever cruise ship Oasis of the Seas, due to be launched in the USA in December 2009, and capable of carrying more than 5,000 passengers.

Tony Childs, commercial director for the firm, said the market was growing – but its core demographic was shifting.

He said: 'The historic profile for people on these kinds of vessels has been 60-plus, empty nest, who have paid off their mortgage. That's changing significantly, and we have a lot more families now than there used to be.

'They are basically resort holidays, floating resorts. Water-parks, gyms, spas – the facilities on these ships now are just incredible.'