Melody Caddick is rapidly assembling a Lego koala.

She designed it, a nod to her Australian roots, but she has moved on to other projects now, and she actually has to keep checking the instruction booklet for how to put the piece together.

We meet the 40-year-old Queenslander at Lego headquarters in Billund, Denmark, but not in her office.

Not even her partner is allowed in there.

Young children can enter the design team's work area, but otherwise it is out of bounds because of commercial secrecy.

Ms Caddick is one of those rare people doing the job they dreamed of as a young child.

It began when she was six years old, when she received her first Lego set as a gift from her grandparents.

So besotted was she with the toy, that even at that age she began thinking about how she could one day get to Lego headquarters and secure a job there.

At that point, it seemed like a pie-in-the-sky dream.

"I got out the atlas and I looked at the atlas and it's like, 'OK, we're here and Denmark's all the way over there'," she said.

"It's a long distance, so I didn't think anything would ever eventuate into anything."

But her love of Lego and her desire to work there never dimmed, and Ms Caddick became what is referred to as an AFOL — that's an Adult Fan of Lego, for the uninitiated.

A freshly made box of green Lego produced at the headquarters in Denmark. ( ABC: Barbara Miller )

AFOLs collect sets, build, design and communicate with one another through online forums and magazines.

There are thousands of them around the world, but very few get to work at Lego.

Ms Caddick achieved her dream by first relocating to Europe and then getting a foot in the door at Lego as a personal assistant.

Then she, like all other hopefuls, had to submit a portfolio of her work and get through several days of rigorous recruitment workshops.

When she got the call saying she had been successful, she could hardly believe her luck.

"I remember the phone conversation and I remember thinking, 'Really? No way'," she recalled.

She still loves her work with a passion.

"Sometimes it's actually very hard to leave for the day," she said.

A Lego designer is a highly prized position, and not just outside the company.

"I think it's a job that a lot of people, also internally in the Lego group, are quite envious about," company spokesman Roar Rude Trangbaek said.

"I would love to work as a Lego designer, but I am simply not creative enough or good enough a builder to do that."

The Lego brick's historic rise to fame

An automated machine at the Lego factory that gathers fresh batches of bricks. ( ABC: Barbara Miller )

Lego is sold in more than 140 countries, and in 2014 net profits were up around 15 per cent to $1.5 billion.

Not bad for a company still in family ownership, which began producing wooden toys in the 1930s.

But plastic slowly replaced the wood, and Lego's success grew and grew.

Turn the clock back 20 years or so however, and times had become tough.

"If you want to boil it down to one thing, it is probably that we lost faith in the Lego brick," Mr Trangbaek said.

A period of diversification followed, with the company investing in Lego parks, books, branded clothing and computer games.

"All of these things combined made a cocktail that wasn't really good for the company," Mr Trangbaek said.

These days Lego is focusing on its core business again, leaving the spin-offs to commercial partners.

"A part of our turnaround, which began in 2003 to 2004, was actually refocusing on what Lego play is all about," Mr Trangbaek said.

Lego saw itself slammed in the media last year after it refused to supply bricks for an artwork by Ai Weiwei for the National Gallery of Victoria, because the company said it did not support projects which could be seen as political statements.

Earlier this month, Lego revealed to the ABC that it had changed the policy in the wake of that controversy, and in future would supply orders for such projects as long as the buyer agreed to state that Lego did not endorse any resulting public works.

But the company denied the negative headlines harmed business, saying its 2015 results due out in early March will prove otherwise.

That is music to the ears of Ms Caddick, who said she would never leave Lego's corner of Denmark.

"This is where Lego is, so this is where I am," she said.

"As long as they're there, I'm there."