It's a concept that has many drivers tearing their hair out.
Do I stop? Do I go? Do I let that guy in? What's that woman doing pushing in?
The commonly misunderstood road rule is cleared up in this week's Road Rule Rumours column.
If you think the vehicle in front has right of way when merging, or that drivers should automatically give way to the car merging on the right, think again.
"This is not the rule; who has right of way when merging is determined by the road markings," Acting Sergeant Mark Johnston of the Sunshine Coast Road Policing Unit said.
"On a road where there is more than one lane of traffic and the driver's lane comes to an end, you must give way to the traffic already in the lane beside you.
"If you are travelling in the lane that is ending and your vehicle is in front of the other vehicle in the lane beside you, this does not mean that you have right of way.
"You need to treat this situation as if you are changing lanes, meaning that you must give way to traffic already in that lane."
Which option best describes your merging style?
This poll ended on 30 April 2015.
Ready or not- here I merge!
I'd better let that guy through first, oh and that guy too...
I know how to get across without crossing the law
This is not a scientific poll. The results reflect only the opinions of those who chose to participate.
The rules change when there is more than one lane and both lanes merge into one with no road markings.
"On a road where there is more than one lane and both lanes form one lane with no road markings, the vehicle in front has right of way, meaning that if the driver is travelling slightly behind a car in the lane beside them, the driver must give way to the vehicle that is in front of their vehicle," Acting Sgt Johnston said.
"In simple terms, the vehicle in front has right of way.
"Failing to give way while merging can cause a serious road crash, especially when the speed limit is 100kmh."
A driver who fails to give way when changing lanes can be fined $341 and three demerit points.
A driver who fails to give way when lines of traffic are merging can also be fined $321 and collect three demerit points.
Update your news preferences and get the latest news delivered to your inbox.