The Welsh Assembly Government has given the final go-ahead for a controversial cull of badgers in an attempt to combat bovine TB infections.
The cull, along with more frequent testing, will take place in a pilot area, mainly in Pembrokeshire.
The move has faced bitter opposition from some animal welfare campaigners, including the Badger Trust which is seeking legal action over the move.
Opposition parties in the assembly have backed the decision.
Making the announcement, Rural Affairs Minister, Elin Jones said: "Bovine TB is out of control and unsustainable and last year cost the taxpayer nearly £24m in compensating farmers.
"We know that cattle and badgers are the main sources of the disease and that, if we want to achieve our aim of eradicating bovine TB, we have to tackle the disease in both species.
"The approach we will be taking in the pilot area, carrying out a badger cull alongside strict cattle controls, has not been tried before in the UK.
"However, it is proving successful in countries like New Zealand, where wild possums and cattle are the main sources of infection."
The cull area covers 288km² (111 sq-mile) of north Pembrokeshire, and a small part of Ceredigion and Carmarthenshire.
The assembly government said these areas had "endemic" TB infections, with 42% of cattle owners having at least one case of the disease in their herd since 2003.
It added that while only 700 cattle were destroyed because of TB in 1997, this had increased by 12,000 cases in 2008.
The government also said that alongside the badger culling, there would be stricter cattle control measures in the cull area.
It also said that there would be a wide scale evaluation of the impact in the area, with post-mortem examinations of badgers, and detailed investigation of every cattle TB incident.
However, campaigners Badger Trust announced in December that they were launching an application for a judicial review against any possible cull.
Responding to Wednesday's announcement, a Badger Trust spokesperson added: "We rather hoped they would hold on until the legal thing was resolved, but I must stress they don't have to.
"We stand on science - whether in fact, and how far, badgers are implicated in the transmission of bovine TB and whether the eradication of the badger population would significantly contribute to the eradication of bovine TB.
"And we say that has not yet been proved, and quite the contrary."
But the Farmers' Union of Wales (FUW) supported the decision.
"This final ministerial decision marks an important step towards reducing bovine TB incidences in an area that has one of the highest rates of the disease in Europe," said FUW spokesman, Brian Walters.
The Conservative's rural affairs spokesman Brynle Williams AM was also supportive.
"While I don't want to see the wholesale slaughter of wildlife, I recognise that we cannot afford to sit back and ignore the very real threat posed by bovine TB to animal health and the farming industry," he said.
Welsh Liberal Democrat leader Kirsty Williams echoed his view, adding: "For many farmers, the emotional and financial strain can be too much and I'm glad that the Welsh government is taking this issue seriously."
However, two members of her own party in the assembly have voiced their continuing opposition to the cull.
South Wales West AM, Peter Black, and Cardiff Central AM, Jenny Randerson both called for any decision on a badger cull to be postponed until the Badger Trust's legal challenge has been heard by the courts.
"Although some members of the Welsh Liberal Democrats support this cull it is not and never has been party policy," said Mr Black.
"I have been approached by a lot of party members who are not happy with the decision and who are opposed to it."
Ms Randerson added: "In England, on the basis of the same evidence available to our Minister, a decision has been taken not to have a cull. Why is it that two different Ministers can come to different conclusions when faced with the same facts?
"The minister should respect the judicial process and halt her preparations until the latest challenge is resolved."