A £650 million scheme will cut train times between Scotland's two major cities as well as creating hundreds of jobs.
The Edinburgh Glasgow Improvement Programme (EGIP) will see the line between the two cities electrified, reducing journey times by 10 minutes and improving reliability.
The Edinburgh to Glasgow Queen Street service that goes via Falkirk High station should take 40 minutes when the improvements come into effect in 2016. In addition, transport chiefs are promising longer trains on the key route while passengers will benefit from having wi-fi on all trains on it from the end of next year.
Transport Minister Keith Brown said the improvements would "take train journeys on Scotland's busiest commuter route into the next generation".
He added: "These enhancements to the service will be a massive boost for both cities, and all the communities which surround them, as well as benefiting Scotland's economy as a whole through additional jobs and investment. Of course, passengers will enjoy quicker journeys, full wi-fi connectivity and better trains."
As well as improving the Glasgow to Edinburgh service, plans are in place to revamp Queen Street station, with the existing platforms to be extended to accommodate longer trains.
A new Edinburgh gateway station will link the rail line to trams in Scotland's capital and should also improve transport connections to and from the city's airport. Meanwhile, the Glasgow to Cumbernauld rail service will be electrified in time for the 2014 Commonwealth Games.
Details of the improvement programme were announced by Mr Brown on a visit to Queen Street station. He said the improvements would "not only secure faster times between Edinburgh and Glasgow, they will increase capacity, revitalise Queen Street station and protect local commuter services into Glasgow".
Changes to the EGIP scheme mean savings of £300 million on the original cost have been made, with Mr Brown saying it would "save hundreds of millions for the public purse".
Glasgow City Council leader Gordon Matheson said: "Improvements to the service between Glasgow and Edinburgh will bring significant benefits to both passengers and to business."