In the hospitality industry, seasoned professionals liken restaurant years to dog years: one year for a venue is like five years in any other industry.

So Woollahra's Bistro Moncur chalking up a 30-year milestone is quite an achievement at a time of historic challenges within the industry.

The combined effects of lockdowns, staffing shortages and record inflation have threatened the survival of many Sydney restaurants, claiming several high-profile venues including Haymarket's Golden Century and Sydney's Marigold.

Community is key to Bistro Moncur's longevity. A third of the tables are reserved for regulars, some of whom visit up to three times each week. Staff know their names, their preferred seats and how they like their favourite dishes (substitutions welcome).

Over the years they have brought their children, and now their grandchildren, to dine on menu fixtures such as French onion souffle, says restaurant manager Simon Tebbs.

Their loyalty during the pandemic helped the restaurant retain most of its staff.

"The dedication it requires is insane"

Maurice Terzini, Icebergs

But Bistro Moncur is far from the only iconic Sydney restaurant to overcome the odds.

Later this year, Sean's Panorama will also turn 30. And while owner and head chef Sean Moran puts the success of his salty-chic North Bondi restaurant down to luck, others have revealed the painstaking efforts restaurateurs make to survive and thrive with each new generation.

"The dedication it requires is insane," says Icebergs owner Maurice Terzini, whose Bondi restaurant celebrated its 20-year anniversary last December.

"Sometimes I feel as if it has ripped out my heart and all of my energy.

"Have I been the best father? Probably not. Have I been the best partner? Probably not. I'm always focusing on work."

Diversification has proven critical to the Icebergs business model. Chef collaborations, a strong bar offering and glamorous New Year's Day parties have helped keep the two-hatted restaurant fresh and front of mind.

"But we've had our fair share of problems," Terzini says.

The oceanside restaurant, which underwent an eight-month renovation last year, has racked up eye-watering maintenance bills due to rust and corrosion ("It's like a f—ing ship," says Terzini), TikTok outrage over a $68 pasta dish and a COVID rent deferral bill that will haunt the restaurant for many months to come.

"It has taken us 20 years, but Icebergs 2.0 has really found its feet. After 20 years, I finally feel like there's less room for error, more consistency and the room has calmed down."

And there's no slowing down: As the restaurant takes in "record figures", Terzini brainstorms new ways to use the Icebergs name. A pop-up bar in Ibiza, perhaps? Or a resin serveware collection?

At three-hatted harbourside restaurant Quay, which last year celebrated 20 years with chef Peter Gilmore at the helm, "it's not really about revolution, it's about evolution".

"We make changes slowly but thoughtfully. I have extra time as a resource because the restaurant is so successful, and that's what enables me to push boundaries," Gilmore says.

Jeremy Courmadias is the CEO at hospitality group Fink, which brought Gilmore on board as Quay's head chef in 2001. He says the restaurant's greatest challenge is remaining relevant.

"We are on a continual path of growth, always looking for new ways to tweak and change the customer experience," he says.

"We're coming up to the five-year anniversary of our renovations, which means we're going to have a good, hard look at everything we offer.

"Are we still relevant? Do people still want set menus? How can we remain at the forefront?"

At 22-year-old Fratelli Paradiso, owners Giovanni and Enrico Paradiso rely on their community to remain relevant. They say they have worked hard to connect with and evolve alongside each new generation of customers.

"It's a sense of understanding of time and place, and not being dictated by any type of fad," Enrico says.

"The food and beverage program is always evolving but it does have this great familiarity about it," Giovanni says. "We'll have people go overseas and come back 10 years later and this place still feels like home."

But longevity comes with its own challenges.

While Bistro Moncur head chef Tom Deadman added new dishes such as Murray cod with chickpea panisse and vongole to the menu this month, Tebbs feared "burning torches and pitchforks" should the kitchen drop any of the regulars' favourites.

Deadman says the change was necessary to attract younger kitchen talent.

"We have a fantastic core team … but not too much interest from bright young chefs," he says.

"Hopefully bringing in a new menu brings us back to the forefront of people's minds."

Fratelli Paradiso, Potts Point

Years of operation: 22

Signature dish: Spaghettini with roast scampi, cherry tomato, napoli & bisque

Tip for longevity: Understand you can't change what's happening outside of the restaurant, so concentrate on what's happening within your four walls.

Bistro Moncur, Woollahra

Years of operation: 30

Signature dish: French onion souffle gratin

Tip for longevity: Give customers what they want, not what you think they should have.

Quay, The Rocks

Years of operation: 22 (with Peter Gilmore)

Signature dish: Confit pig jowl with black pearl mushrooms, southern squid, sea cucumber and smoked trotter broth

Tip for longevity: Play the long game. A great restaurant is not made in the first year, or even five years … Understand there will be ebbs and flows and that's okay, that's part of it.

Icebergs, Bondi Beach

Years of operation: 20

Signature dish: Risotto al gamberi

Tip for longevity: Be prepared to give everything up. A restaurant requires 100 per cent dedication.

Sean's Panorama, North Bondi

Years of operation: 30

Signature dish: Roast chook with seasonal vegetables

Tip for longevity: Drop the ego. Running a restaurant is not competitive, rarely lucrative and the demands are challenging — it's a way of life, so be true to your intuition and there will be moments that completely fill your heart with joy.