The Treasurer should be able to take television cameras, for instance, on walks down George Street.

Had Berejiklian, as transport minister between 2011 and 2015, not forcefully backed construction of a light rail line in the heart of the city, that line would not be under construction. By 2019, it should be completed.

Ms Berejiklian may have spent the past two years as Treasurer, during which she has handled the biggest privatisation in the state's history, but she is probably best known for her time as transport minister.

In that position she presided over certain radical changes, yet also built a reputation for diligence and conscientiousness. The fruits of many of those changes, potentially good and bad, are set to be borne in her early years as premier.

When Berejiklian entered the transport portfolio in 2011, after four years as the opposition spokeswoman, she decided to hang onto the top ranks of the public service.

She retained Les Wielinga, a long-standing roads bureaucrat, as the head of the department. And she retained Rodd Staples, who had run Labor's ill-fated metro, which Berejiklian had criticised fiercely, and put him in charge of her rail-building program.

"I guess when she came in, many of us thought she would make some changes in the bureaucracy, but in fact she didn't do that," says Patricia Forsythe, a former Liberal MP who mentored Berejiklian in her early parliamentary years.

"She gave them trust and I think she got enormous loyalty from a number of people," says Forsythe, now the executive director of the Sydney Business Chamber.

Multiple senior public servants who have worked for Berejiklian say she and her staff were unusually careful in separating political considerations from policy ones.

"From a governance perspective she was fantastic," says a senior public servant who, after working with six premiers and 14 transport ministers, describes Berejiklian as easily the best of them.

"She was very, very clear about where the boundary was [between political and policy questions]," the public servant says. "If it was a political issue, she would deal with it."

It may yet be, however, that decisions taken on policy grounds will continue to have political ramifications.

Some time next year, for instance, the Epping to Chatswood rail line will be closed for six months or so to allow its conversion to a "metro" line. That closure is the result of Berejiklian's decision to break a pre-2011 promise and build an $8.3 billion rail line to the north-west in a manner that is incompatible with the rest of the rail network.

The policy benefit will hopefully be a more reliable rail line that is also cheaper to run; the political cost, however, will be in the tens of thousands of people without a train line for half a year or more.

But Berejiklian became used to difficult decisions in her time as transport minister. To win cabinet approval for the light rail line, she had to overcome the fierce rearguard resistance of Infrastructure NSW, the advisory body then chaired by Nick Greiner.

"If you add light rail to George Street today, you will not fix a problem, you will create a problem," the chief executive of Infrastructure NSW, Paul Broad, said at the time.

During her time as transport minister, Berejiklian also secured support for an over-arching transport scheme for Sydney's central business district. Her government has dragged its feet on implementing it, but the Central Sydney Access Strategy has committed the state, for the first time, to a grid of separated bike paths throughout the central knot of the city.

That transport strategy was also released under the name of Duncan Gay, the Roads Minister, who had been a well-known sceptic when it came to bike lanes.

But Gay says Ms Berejiklian and he worked "pretty damn well" together during her years in transport.

"I love her as a person," Gay says.

"Glad and I didn't agree on everything but the great thing was that, if she won the argument in cabinet, I would support it and vice versa," he says. "You put your case as strong and as hard as you can and, if you don't win, you support the person who won … she is just incredibly loyal when it comes to those things."

And what will she be like as premier?

"Everyone works hard, she puts the extra step in," Gay says.

"She won't be Barry, she won't be Mike, she'll be Glad. People tend to like Glad."