How do they do it? Try friendship and fun, Murray Cook (the red one) tells Shane Gilchrist.
As a parent and a performer, Murray Cook gets more than his fair share of childish glee, those looks of joy that spread across a youngster's face and arc and spark elsewhere, as spontaneous and contagious as a yawn.
Though The Wiggles have been performing for 18 years, there's plenty of gas left in the tank of their (toot, toot, chugga, chugga) big red car.
Certainly, Cook has yet to tire of the songs, the characters and the tours. Children (and plenty of adults) feel the same way.
Pre-school facilities are unlikely to be overburdened come The Wiggles' two shows at Dunedin's Regent Theatre on Tuesday, April 7.
So how do they remain fresh, professionally and personally? "Playing live is a big part of it," Cook explains via telephone from The Wiggles' Sydney offices.
"You are always in front of audiences. You're always trying to come up with new things.
"Kids are so willing to a have a good time, too. They want to have fun. Sometimes if you play in a band with adults, the audience of adults will stand back. They'll say, `impress me and I'll respond'.
"But kids are into it right from the start - and if they are not, they'll walk away. There is no politeness. Fortunately, we don't seem to have that problem."
In 1991, Cook met Anthony Field (Blue Wiggle) and Greg Page (the original Yellow Wiggle) while studying early childhood education at Sydney's Macquarie University.
The three began writing children's songs as a music project, enlisting the help of Jeff Fatt (Purple Wiggle), who had played with Field in popular 1980s band The Cockroaches.
That year The Wiggles took their first demo tape to ABC Music, which released their self-titled album.
It turned out to be a good investment: The Wiggles have now sold more than 23 million DVDs and seven million CDs worldwide.
But progress hasn't always been smooth. In December 2006, Page left the group because of an ongoing illness, handing over his yellow skivvy to Sam Moran, who had been touring with The Wiggles for almost 10 years, firstly as the host of the Dorothy the Dinosaur Show and then joining The Wiggles as a dancer and Greg's understudy.
Strong friendships have been a key to the outfit's longevity, Cook says.
"It is definitely like family. We've been together so long that we know each other really well. We are friends. It was a genuine thing we wanted to do. We weren't put together by the media or something.
"It was just four guys who wanted to try something and it became successful. I think people respond to that. I think people recognize there is a genuine friendship among us."
Though Cook says The Wiggles are always looking for new creative approaches - they recently recorded a song with Kylie Minogue - it is important to retain the show's essence, be that via live performance, DVD or CD.
"I guess a lot of it is making it familiar for children. One of the things we do is we try to empower them as well - like waking up Jeff if they see he has fallen asleep. We tell them that we need their help to wake him up, so they feel part of it.
"Kids can interact with us, particularly in a live situation. We can respond to them if they say something back to us. I think young children love the fantasy characters but they do respond to humans. We are programmed to respond to human faces."
Dorothy the Dinosaur's more recent visits notwithstanding, the last time The Wiggles made a full tour of New Zealand was in 2005.
"It is a while back . . . we always like coming over but I'm not actually sure why it's been so long," Cook concedes.
"We haven't done any shows since Christmas so we're really itching to get out on the road again."
Such is the popularity of The Wiggles they have had to post a plea on their official website, asking parents to understand the demands on their time and not to put at risk their children's health by waiting outside, in all kinds of weather, to meet the entertainers.
"There was a bit of craziness in America, mainly in theatres where our tour bus would be parked near the stage door so they knew where we would come out. It would be snowing or raining and they'd be there with little kids. It was just getting a little dangerous, so we just put that on the website so that people would think a little bit more.
"I think that celebrity culture thing is bigger in America. We don't even think of ourselves like that, but they really do want to meet the people they see on stage. I think the way we present ourselves in the videos is fairly friendly; we do talk directly to the camera, so people feel like they know us."
Win tickets
They are the best thing to come out of Australia since, well...ever.
The Wiggles are playing their first gigs in Dunedin for ages and the Otago Daily Times has great tickets and prizes to give away.
The band performs at Dunedin's Regent Theatre on Tuesday, April 7.
There are two shows, 10am and 12.30pm. We have tickets to the first show.
First prize is four tickets to the show, as well as the opportunity to meet The Wiggles beforehand.
Second prize is four downstairs tickets to the show, and third prize is four circle tickets to the show.
Each prize comes with a Wiggles DVD.
To enter the draw, write your name, address and daytime phone number on the back of an envelope and send it to The Wiggles, ODT Editorial Features, Response Bag 500011 Dunedin, or email playtime@odt.co.nz with Wiggles in the subject line, to arrive before Thursday.
