Lavish fireworks displays have ushered in 2013 across the Asia-Pacific region and Europe is holding scaled-back festivities in the hope of beginning a new year that will be kinder to its battered economies.
Asian cities kicked off New Year's celebrations in style and an atmosphere of renewed optimism, despite the "fiscal cliff" impasse of spending cuts and tax increases threatening to reverberate globally from the United States.
Huge fireworks lit up skylines in Sydney, Hong Kong and Shanghai, and even the once-isolated country of Burma joined the countdown party for the first time in decades.
Celebrations were planned around the world, including the traditional crystal ball drop in New York City's Times Square, where a million people are expected to cram into the surrounding streets.
In Russia, Moscow's iconic Red Square was filled with spectators as fireworks exploded near the Kremlin to welcome in the new year.
Earlier, about 25 people were reportedly arrested in Moscow for trying to hold an unsanctioned demonstration. But President Vladimir Putin gave an optimistic New Year's Eve address, making no reference to the anti-government protests that have occurred in his country in the past year.
"We believe that we can change the life around us and become better ourselves, that we can become more heedful, compassionate, gracious," Putin said, according to the ITAR-Tass news agency.
In Australia, a balmy summer night was split by seven tons of fireworks fired from rooftops and barges in Sydney, many cascading from the city's Harbor Bridge, billed as the world's largest.
In Burma, after nearly five decades under military regimes that discouraged or banned big public gatherings, about 90,000 people experienced the country's first New Year's Eve countdown in a field in the largest city of Yangon.
"We feel like we are in a different world," said Yu Thawda, a university student.
Tens of thousands of people lined Hong Kong's Victoria Harbor to view a fireworks display, said to be the biggest ever in the southern Chinese city.
In North Korea, cannons boomed at midnight in Pyongyang as people crowded the streets of the capital to watch a fireworks show over the Taedong River. After being in mourning a year ago regarding leader Kim Jong Il's death, North Koreans celebrated the end of a big year that included the rise of new leader Kim Jong Un and the recent launch of a satellite into space.
Hotels, clubs and other sites in New Delhi, the Indian capital, cancelled festivities after the death on Saturday of a young rape victim touched off days of mourning and reflection about women's safety. People were asked to light candles to express their solidarity with the victim.
In Indonesia, Jakarta's street party centred on a four-mile thoroughfare closed to traffic from nightfall until after midnight. Workers erected 16 large stages along the normally clogged, eight-lane highway through the heart of the city.
Indonesia's booming economy is a rare bright spot amid global gloom and is bringing prosperity - or the hope of it - to its people.
In austerity-hit Europe, the mood was more restrained - if hopeful. The year 2013 is projected to be a sixth straight one of recession amid Greece's worst economic crisis since the second World War.
In fact, the new year was starting with a 24-hour strike by subway and train workers in Athens to protest salary cuts that are part of the government's austerity measures.
Still, in his televised New Year's Eve message, Prime Minister Antonis Samaras promised Greeks that the worst of the crisis is past, and declared 2013 a "year of hope" that will see the beginning of the country's rebirth.
Celebrating New Year's Eve with a vespers service in St Peter's Basilica, Pope Benedict XVI said that despite all the injustice in the world, goodness prevails.
German Chancellor Angela Merkel's New Year's message warned her country to prepare for difficult economic times ahead. Nicosia, the capital of Cyprus, decided to cancel celebrations in light of the economic crisis. Nicosia said the money saved from the cancelled event will be given to some 320 needy schoolchildren.
In Spain, where a recession has left unemployment at a staggering 25%, people are hoping for a better new year.
"It's been tough, but some celebrations are too deeply-ingrained to let go," said Olga Camino, 25. She said she would be celebrating in the streets of Madrid in fancy dress with a large group of friends.
Camino said they would all eat 12 grapes as the clock in Madrid's central Puerta del Sol struck midnight, a tradition observed throughout Spain.
Scotland's Edinburgh, which traditionally hosts one of the biggest New Year's Eve parties in Europe, also planned good cheer. Festivities for the three-day Hogmanay celebrations began with a torchlight procession in the Scottish capital, and organisers said about 75,000 people are expected to line the streets for Tuesday's fireworks.