Belfast is the most congested city in the UK - and the 14th worst in the world - with drivers spending an average of more than eight days a year stuck in traffic, a study has found.
The TomTom Traffic Index, which analyses congestion in cities around the world, has said Belfast has more serious hold-ups than London, Manchester and Edinburgh.
The study says that average journey times in the city are 40% slower than if traffic was moving freely.
During the evening rush hour this rises to 86%, up from an 80% figure the previous year.
Drivers in Belfast are now wasting an average of 195 hours a year behind the wheel, more than eight days. This is double the figure suggested in the same study last year of 94 hours, or nearly four days.
Roger Pollen from the Federation for Small Businesses said a new approach is needed.
"It's hugely frustrating, but it's not at all surprising and I think it's interesting to see the study showing that amount of capacity lost," he said.
"Not just the capacity of business owners and staff, but also customers not being able to get into the shops and so on. Then there's the associated impact of that amount of static traffic."
Mr Pollen said efforts to get Belfast commuters to use more public transport wasn't working.
"The general consensus was that there's a lot of concern that Northern Ireland's very much a rural population. If people are travelling into the city to work and to shop then an awful lot of the public transport provision is not sufficient to do that.
"In many ways the focus should be on how to accommodate cars better rather than to make the city hostile to cars. ."
On the issue of bus lanes, he pointed to Liverpool who abandoned their bus lane policy.
"You've got to ask how long do we persevere with ours and see the figures getting worse and worse before we start looking at what other measures we bring in to make the city more effective for cars." This month, the Transport Minister Michelle McIlveen announced a tender process for a £130m scheme to upgrade the York Street interchange, one of the busiest traffic areas in the city.
The works would build a new underpass and bridge, to improve traffic flow where the Westlink, M2 and M3 meet. Construction is expected to start next year and be completed by 2020.
Mr Pollen welcomed the scheme but added: "There has to be another large raft of measures to make Belfast a welcome place for people to come and do business."
Ralf-Peter Schaefer of TomTom Traffic said: "Building new motorways and ring roads doesn't eliminate congestion. More must be done to better manage existing road space."
Source: TomTom Traffic survey