The old fundamental principles must continue to apply, even in our changing society: Democracy knows neither master nor slave. Equal education opportunities for all, no matter where they come from and no matter who their parents are. Equal access as well when it comes to digitalization.

When we were negotiating the ongoing financial period in 2013, I talked myself hoarse. London and Berlin in particular insisted on reducing the budget. So we - to the applause of German journalists - made cuts to central future-oriented areas and slashed the budget for development aid, research and technology.

Referendums are a democratic instrument, but so are decisions reached in a parliamentary democracy. I advise extreme caution when it comes to referendums. In Germany too.

Things are going well in Germany because the economy is booming and as an export-driven nation, we are profiting from the fact that we have an excellent, high-performing SME sector. But if we want things to continue to go well into the future, then we have to break up the antiquated structures in some areas and really modernize.

The principles of the SPD have remained the same for 150 years: democracy, human dignity, justice and inclusion. We will never change those principles.

My worry is that Donald Trump may inspire copycats, also in Europe. That's why I hope Hillary Clinton wins.

The construction of social housing and the attempt to support families seeking to buy their own homes are all projects from the 1960s and '70s. It all sounds old-fashioned, but it is actually completely modern.