Mauricio Macri is about to take over as president of Argentina, promising to exploit its vast natural resources and to abandon his predecessor's policies to revive an economy.
If Macri, who will be sworn in at midday on Thursday, gets it right, investment could stream into Latin America's third-largest economy, given its pampas grains belt, promising technology sector, highly educated workforce and some of the world's richest shale oil deposits.
Outgoing leader Cristina Fernandez de Kirchner is from the populist tradition of Juan Domingo Peron, and his wife Evita, who expanded the reach of the state in the 1940s.
Thousands of supporters thronged Argentina's most famous square on Wednesday to say goodbye to Kirchner, who made her last public address before handing over power.
She gave a speech to supporters about the successes under her leadership that was both a recap of her years in power and a clear sign that she does not plan to make things easy for Macri.
In her speech, Kirchner criticised a federal court ruling on Wednesday in a case brought by Macri that determined her presidency ended at midnight, saying it would leave Argentina without a president until Macri's swearing-in.
"I can't talk much because after midnight, I'll turn into a pumpkin," she joked.
During her eight years in power, Kirchner ringed Argentina with protectionist trade policies meant to bolster local industry.
She increased welfare spending at a time when millions of Argentines needed help climbing out of poverty after a devastating 2002 economic crisis.
Aided by high world grain prices, her first years in power saw strong economic growth. But the end of the commodities boom combined with heavy government spending and currency controls, hit growth and pushed up inflation to well above 20 percent.
Kirchner will not be attending the handover ceremony because of a dispute over where the ceremony should take place.
Macri is expected to face many challenges including the turbulent state of the economy.
He has pledged to kick-start the economy by ending protectionist import restrictions, cutting heavy taxes on agricultural exports and scrapping the official exchange rate propping up the Argentine peso.
Macri, who ran on a free-market agenda, beat Kirchner's chosen successor by three percentage points in a run-off election last month.
The close result underscored the deep polarisation in Argentina, and Kirchner has made clear she will continue to be heard, albeit from the sidelines of power.