The BBC is to invest an extra £8.5m a year in English language television programmes for Wales.
It follows a campaign to boost spending in the area, with politicians and lobbyists calling for an extra £30m.
The BBC said the new investment was a 50% increase and would fund new drama, comedy and entertainment programmes.
BBC Director General Tony Hall said: "BBC Wales has a remarkable creative track record and I know they'll seize this new opportunity with real relish."
Lord Hall added that he believed the investment would be "transformational".
He said: "In areas such as drama, comedy and entertainment, we expect to more than double investment. In news and current affairs, it will help us move faster online and reach out to younger audiences, and provide greater specialist reporting across our output.
"It's so important that the BBC captures the real diversity of life and experience in Wales, and this investment is a real statement of intent about our ambition to serve all audiences in Wales."
The most recently published budget for BBC Wales English language TV was £22.5m in 2015/16.Image caption Richard Harrington and Mali Harries in Hinterland, a co-production with S4C
The cost per hour of programme was £35,200.
First Minister Carwyn Jones and the Institute of Welsh Affairs have previously called for £30m of additional investment, while the assembly's culture committee recently echoed those requests.
The campaign for extra funding was prompted by a speech given by Lord Hall in Cardiff in 2014 in which he said English language TV programming in Wales had "eroded" over the past 10 years.
New programmes funded by the budget increase will include two "major" new dramas, details of which will be announced in the coming days.
The money will also be used to improve news services, including plans to expand BBC Wales's specialist coverage, as well as its online and mobile services.
The investment is expected to generate around 130 hours of programming to be broadcast on BBC One Wales, BBC Two Wales and BBC iPlayer.Image caption Naturalist Iolo Williams in Iolo's Great Welsh Parks
BBC Wales says it hopes at least half the additional programming will also be broadcast on the BBC's UK-wide channels, helping to boost the portrayal of Welsh life on network television.
Labour AM Lee Waters, who was director of the Institute of Welsh Affairs (IWA) when it concluded in 2015 that £30m should be invested in the BBC's services in Wales, said the funding returned its spending to the levels seen in the mid-2000s.
"The BBC's announcement takes it back to the sort of levels they were spending a decade ago, before they started slashing the budget for English language programmes in Wales," he said.
"I warmly welcome Tony Hall putting an additional £8.5m into programming for Wales by 2020, but it is worth noting that this sits alongside their recent announcement of £9m worth of 'efficiencies' in BBC Wales, and falls well short of the additional £20m that the first minister, the Assembly's culture committee and the IWA's substantial media audit called for.
"That said, it will deliver improvements on what was planned before pressure was put to bear, and I'm pleased that the ambition is to target the funding on quality programmes that can earn their place on the main BBC network so that Welsh stories can be seen and heard across the UK."Image caption Dan Snow on Lloyd George: My Great Great Grandfather Image caption Gareth Wyn Jones: Milk Man explored the struggles in the dairy industry
BBC Wales Director Rhodri Talfan Davies: "This new investment is tremendously welcome. Wales is blessed with superb storytellers, and this investment will give them a fitting national stage.
"By the time we move to our new home in Central Square in less than three years' time, I believe the difference on screen will be clear to audiences the length and breadth of our nation."
"The new investment package will also allow us to attract greater co-production investment, using the collaborative models we've developed with S4C and others to fund series like Hinterland."
Bethan Jenkins, chairwoman of the Senedd Culture, Welsh Language and Communications Committee, told BBC Wales: "It has been a long time coming. We do welcome any investment, and a 50% increase is something we will look forward to being spent here in Wales on new programming.
"But we would say it falls short of the £30m a year increase we wanted to see - not only us, but the IWA and the former Assembly equalities committee also called for that £30m.
"I would be interested to see how the money is going to be spent, whether it will actually make the difference that we need to be seeing in programming across the board, and then we would like to question Lord Hall further when he comes back to our committee in March."