Two months after the SPD beat Angela Merkel's conservative CDU-CSU coalition in a general election, its negotiators put the finishing touches on the deal with the Greens and liberal Free Democrats that will install Finance Minister Olaf Scholz, 63, as chancellor.
The relatively rapid accord is likely to be greeted by a heave of relief by international partners wary of a hamstrung Germany while crises from the coronavirus pandemic to Belarus and a weak economic recovery rage.
Critical voices within Germany have grown louder for greater urgency from the new coalition to curb a surging fourth wave of the pandemic as hospital beds fill up and new infections soar to records highs day after day.
In a sign of the emergency, Merkel, who is retiring from politics after four terms, summoned the leaders of the new coalition parties for talks over the rapidly deteriorating Covid situation midway during their last spurt of negotiations Tuesday.
On Wednesday, the parties said they will meet for a "final session" of talks.
"Afterwards, the leaders of the three parties and the candidate for chancellor, Olaf Scholz, will present the coalition agreement negotiated in recent weeks," they added.
With the so-called coalition contract, the parties have essentially set their policy roadmap for the next four years.
Expected to feature in the agreement along with their stance vis-a-vis foreign policy will be a plan to bring Germany's exit out of coal forward to 2030 from 2038 and a proposal to legalise recreational use of cannabis.
Negotiators are also likely to have resolved a thorny part of the talks -- which party takes which ministry.
Latest lists leaked on the ministry distribution show Christian Lindner, leader of the business-friendly FDP, running the powerful finance ministry of Europe's biggest economy.
Robert Habeck, co-leader of the ecologist Greens, is touted to lead a new 'super-ministry' grouping the portfolios of economy, climate protection and energy.
Annalena Baerbock, the Greens' other leader, will likely become Germany's next foreign minister -- the first woman in the job.
The health ministry, which has become highly crucial but also a hot potato during the pandemic, is expected to go to the SPD, according to German media.
The line-up, if confirmed, hints at a Germany that could take a more assertive tone vis-a-vis China and Russia, while economically, it would likely stick to budgetary rigour and aggressively push green investments.
The swift pace at which the three parties -- known in Germany as the Ampel or "traffic-light" after their colours -- came together is a surprise given that the FDP is not a natural partner with the centre-left SPD or Greens.
But the parties are anxious to avoid a repeat of the messy negotiations last time round, when Lindner was vilified for pulling the plug on talks with Merkel's CDU-CSU and the Greens.
Known for her steady hand steering Germany through the eurozone crisis, migrant influx and Brexit, Merkel is leaving office still widely popular with the German electorate.
Mindful of the value placed on a stable Germany, the veteran politician has taken pains to ensure an orderly transition.
Stressing continuity, she included Scholz in key bilateral meetings during the G20 summit in Rome in October including with US President Joe Biden.
When she met regional leaders of Germany's 16 states for urgent talks last week on the pandemic, Scholz was prominently also in attendance.
She has also shrugged aside the fact that Scholz stems from a rival political party, saying she will be "able to sleep soundly" with him as chancellor.
Vote of confidence from Merkel aside, Scholz is an experienced hand, having been labour minister in her first coalition from 2007 to 2009 before taking over as vice-chancellor and finance minister in 2015.
Known for being meticulous, confident and fiercely ambitious, he has cemented his reputation as a fiscal conservative -- something that at times puts him at odds with his workers' party.