JEFF Hamelink wore jeans and a collared shirt to Aurecon's celebration of 20 years in Gladstone on Friday night.
"I love that Gladstone is so casual," he said. "There is no-one inside wearing a tie.
"Hang on, there's one guy wearing one. That's the new boss, but he'll acclimatise soon."
Newly appointed manager of Aurecon's Australian and New Zealand offices Matt Coetzee said he did feel a bit overdressed.
"But once you show up with a tie you have to keep it, don't you?" he said, laughing.
Mr Hamelink is one of four Aurecon employees who have worked in the Gladstone office for more than 15 years.
His colleague Rob Farnsworth has worked for Aurecon "for 19 years, 7 months and 22 days to be exact".
"I always thought I'd be here for a few years and then move somewhere better," he said. "But it turns out the best place is here."
Mr Farnsworth said he remembered the days when chickens would run around the office car park.
"I came from a big city and when I got here I couldn't believe there were no cars in the main street," he said.
Jeff Worland agreed.
He came to Gladstone 25 years ago when Tannum Sands Rd was a beach track.
"They put me up for 12 weeks at the motel and I fell in love with how quiet it was," he said.
"I've been working for Aurecon for more than 15 years and I'm staying for the fishing, fishing, fishing!"
Long-timer Peter Smith's talented daughter Amber Comadina-Smith made engineering-themed cupcakes for the event.
"We moved here with our young family and found it was the perfect place to raise kids," he said.
"As an engineer Gladstone is an amazing place to work, the opportunities and positivity are great."