These are tough times for television drama. The BBC has lopped UK poind 10m off BBC3s budget and pulled the plug on an epic biblical drama and Nicholas Lyndhursts sitcom After You have Gone. Channel 4 may halve the number of episodes in the next series of Shameless, among other cutbacks.

But there is one area that seems almost bullet proof big reality/entertainment shows, such as Strictly Come Dancing and Britains Got Talent. These shiny-floor shows which deliver ratings and cost savings are enjoying a global boom. They are the biggest shows on TV and they played a part in saving Saturday night for UK broadcasters, says Peter Fincham, the director of television for ITV. So far they have played out on the weekends, but I see a lot of potential for these shows to spread out across the schedules and even into midweek slots, as they do in America. They are especially interesting as budgets mean networks are finding it hard to commit to the same amount of drama and (different slots) would mean we were not playing those valuable dramas out against each other in primetime. Bea Ballard, the former BBC creative head and executive producer, who devised 2006s How Do You Solve a Problem Like Maria? the televised search for a star of the West End production of The Sound of Music believes the corporation is also shopping around. Strictly Come Dancing runs for 13 or 14 weeks, (a show like) Maria tends to run for about 10 to 12 which is only about half the year, so there's room for at least two more shows on BBC1, she says.

Ballard, who also created Any Dream Will Do (the search for a Joseph) and I did Do Anything last year, which found two stars for the current production of Oliver, believes Five may do similar shows, after the appointment of the former Sky1 controller Richard Woolfe as its channel head. Ballard says: "When you look at what they deliver compared to drama which is so expensive a big entertainment show can deliver bigger ratings for half the price."

But, as well as being good for costs and ratings, event shows also offer an advantage to broadcasters facing the impact of iPlayer, Sky+ and time-shifted viewing. "With so much download programming available online I think we will only see about 20 of todays 100-odd channels survive," says Ashley Highfield, who created and launched the BBCs iPlayer and founded Project Kangaroo before moving to Microsoft last year.

But they will have to work very hard for our attention. They will have to make fewer, bigger programmes and market the hell out of them. The advantage with event TV is that its not as relevant if you watch it on playback. It is about the here and now and talking about the results the next day over coffee. They could be the key to broadcasters surviving."

Certainly Ballard has reason to hope that entertainment becomes more important her new indie, 10 Star Entertainment, recently opened for business with backing from Fremantle Media. She devised Maria after being struck by the success of The X Factor and The Apprentice the latter was developed by Mark Burnett, who later sold his company for $250m and admits his success helped shape her decision. If I stayed at the BBC then the BBC would own all my ideas and all my shows, she says.

Since the 2003 Communications Act gave indies the international rights to their shows there has been a rush of in-house producers setting up to exploit the worlds hunger for British formats, says Edward Waller, the editorial director of the TV trade title C21. "The UK used to create something like 50% of all formats sold internationally. The problem is countries like New Zealand and Japan are starting to develop strong-selling formats like Japan Hole in the Wall so our share has fallen to 30% in the last year or so. Anyone with a good track record should be looking to set up soon or they might find the door to a fortune closing."

Tim Hincks, the chief executive of the Big Brother producer Endemol, also warns that getting shows right is far more difficult than it used to be. "Even though live non-scripted shows cost between £200,000 and £500,000 per hour, versus upwards of £800,000 an hour for drama, it's a merciless genre if you get it wrong,' he says. Just look at how few entertainment hits have come from in-house in the last five years. Broadcasters will back a drama if they believe in it, but if your format isn't pulling in ratings, you'll be off air overnight and you'll get no sympathy."

There are, however, upsides to making entertainment shows, Hincks admits including the promise of a ratings bonus from US broadcasters if your show hits the top 10 in the ratings.