The Edinburgh Fringe began in 1947 when eight theatre groups turned up uninvited to the first Edinburgh International Festival.
This year about 31,000 performances of more than 2,000 shows will see 18,000 people taking part.
Kath M Mainland took over as the chief executive of the Fringe Society after the previous director resigned in the wake of last year's box office fiasco.
Anyone can perform on the Edinburgh Fringe, what does the Chief Executive do?
I head up the Festival Fringe Society, and our job is to support, encourage and advise all participants, before, during and after the Fringe - provide comprehensive information and ticketing for the participants, the media and the public, and raise the profile of the entire Fringe worldwide through the media and other outlets.
Kath Mainland took over as Fringe chief executive earlier this year
Last year the Box Office was a mess. What are you doing different and how is it going?
We're delighted to report that the box office is going like a fair. We opened on 15 June and have been selling like mad ever since. As of the beginning of the Fringe we are 20% up in terms of ticket sales, so we're extremely pleased about that, and looking forward to a great Fringe in 2009.
What are your first memories of the Fringe?
My first memory of the Fringe is being blown away by the wonderful atmosphere. As a resident of Edinburgh I think it's absolutely wonderful that this enormous explosion of culture happens, each year, right on our doorstep, and that people come from all over the world to experience it with us, here in Scotland.
What is the best thing about the Fringe?
The 2009 Fringe has more than 2,000 shows, across all art forms - theatre, comedy, dance, music, musicals, children's shows, events and exhibitions taking place in more than 150 venues in this great city.
The range of talent and work being put on at the Fringe this year is second to none.
Companies are coming from over 60 different countries to take place and no-where else on the planet can you see such a diverse and exciting range of work, all taking place at the same time, in the same place, and being watched by people who have come here from all over the world to experience it.
It's beyond compare.
Will you be going to see any shows? Which ones?
I'm obviously not going to single out any one particular show! For me the Fringe is about discovery, so a perfect day would be getting to meet people who have come here from all over the world, either to watch or to take part and to discover that gem of a show, lurking in the programme that I can't even imagine at the moment. It really is the greatest show on earth.
You were previously working for Edinburgh's Book Festival, how does the Fringe compare?
It's completely different in lots of ways, but very similar in others! The Book Festival is also an absolutely fantastic event. All the Festivals work extremely closely in Edinburgh, and part of the appeal for audiences is that so much is happening together at the same time, in this amazing city.
Is there competition from other festivals such as Manchester?
Festivals are about the congregation of like-minded people, all experiencing this amazing showcase of work, and they're also about refreshing the creative spirit, and emerging at the other end exhausted but exhilarated.
It's no surprise that other cities have realised the benefits and potentials of putting them on, but I think there is no doubt that Edinburgh is still THE world leading festival city.
It's the original, and it's still the best.
There is nowhere else on the planet that you can experience such a range and breadth of diverse and interesting work, all taking place at the same time, in the same place.
Is the future bright for the Fringe?
The range of talent and work being put on at the Fringe this year is second to none. More people than ever seem to be seduced by the appeal of the Fringe, so yes, I think the future is bright.