If you are one of the 67,000 Sydneysiders who catch a bus into the CBD during the morning peak, be prepared for some changes.
The new CBD bus routes were introduced on Sunday, to iron out the kinks ahead of the rush of commuters expected after the long weekend.
It's all for a new light rail, with a 12km route being dug through the heart of Sydney to make way for the network.
That means George Street is completely closed to buses.
"It's pleasing that this morning has gone relatively smoothly," NSW Transport and Infrastructure Minister Andrew Constance said on Sunday.
"We apologise for the disruption it's going to cause, but I think most people are now saying, `let's get on with it, let's get the build underway'."
Mr Constance says congestion has Sydney's CBD "by the throat" and the problem needs to be addressed before it gets worse.
There were a number of spots likely to see a build-up of traffic, including the usual suspects like the Harbour Bridge, Wynyard and York Street.
"If we're going to see the number of buses on Elizabeth increase from 179 to 201 that's an area which of motor vehicles can avoid it, please do so," he said.
Travellers are asked to jump on the Trip Planner website/app, or speak to one of the `pink shirt brigade' - people offering help to navigate the CBD.
For some people it will mean a longer walk to work, or having to get an extra train or bus.
Mr Constance says the government has commissioned IPART (Independent Pricing and Regulatory Tribunal) to investigate integrated fare approaches.
But his main message is be prepared and be patient.
"This is a transforming city, this is unprecedented for our city...
"Please bear with us."
The light rail is expected to take 220 buses off the roads in Sydney's CBD and accommodate the big increase in commuters expected in the city over the next 10 years.
