Germany expects influx of Polish workers
There may be a celebration of May Day this year in the old communist countries, but not like it once was.
Rather than an unfurling of red flags and workers' banners, this year's ritual may involve the packing of a suitcase and the taking of planes, trains and automobiles to Germany.
When eight ex-communist bloc countries joined the European Union in 2004, Germany and Austria - unlike Britain - opted to postpone opening their labour markets to workers from those countries (Poland, the Czech Republic, Slovakia, Hungary, Estonia, Latvia, Lithuania, and Slovenia).
Now, at the end of the delay allowed by the EU, the doors will be open. The proletariat will be free to migrate to the engine room of Europe. They will be able to work legitimately and openly for wages double and treble what they can get back home.
At the moment, immigrants to Germany need to be hired on a long-term contract by a company, so they tend to be people brought in because of particular skills. They need work permits from officialdom. Casual migration simply to look for work was not allowed.
Not allowed - but done in reality. The change means that the ubiquitous Polish cleaner can come out into the open, emerging from the black economy into the one where there are rights (to protection under labour law) and obligations (to pay tax, should they earn enough).
How the change is viewed depends on where you stand. Employers in Germany view it differently from unions. Workers on the eastern bank of the River Oder in Poland view it differently from workers on the western bank, in Germany. The water is often only a stone's throw wide, but the wage differential is three-fold.
The Institute for Economic Research in Cologne reckons that just over a million people will immigrate to Germany by 2020 - not overwhelming, compared to the three million immigrants in the 1990s, the decade after the fall of the Berlin Wall.
The institute notes, though, that a survey indicated that 40% of German workers feared that their wages would be undercut.
And its estimate of the number of migrants is higher than that made by Germany's labour ministry.
But predicting numbers is notoriously difficult. In Britain, for example, the official estimate before EU enlargement in 2004 was a fraction of what actually happened.
A government report at the time concluded: "Estimates for the UK range between 5,000 and 13,000 net immigrants per year".
By the latest figures, in contrast, the numbers of people living in Britain but born in Poland actually rose by an average of more than 60,000 a year between 2003 and 2010 - a sevenfold increase from 75,000 to 520,000.
Many Poles stayed - and spent. As the supermarket chain Tesco put it: "Try our new range of Polish food and drink online. We stock healthy and tasty food directly from Poland including beer, puddings, snacks and many more". The Polish pound went into British profits.
So the debate in Poland is over what exactly migration will do to the home economy. Will there be a great sucking out of skilled and not-so-skilled workers who will stay abroad and spend their money there?
Germany, of course, is nearer to Poland than Britain is - it shares a long land border, so migrants can return and spend more easily.
Talking about the numbers of emigrants, Poland's Minister of Labour Jolanta Fedak said on Polish radio: "We are looking at 300,000 to 400,000 people, but over a period of three to four years."
She also thought there was an important difference between the ease of access to British work compared to work in Germany. "The German market is quite a demanding labour market, above all requiring those that arrive in the country have a knowledge of the German language."
The Warsaw Business Journal plumped for a figure of "500,000 Poles who are likely to find work in Germany". It thinks emigration will boost the Polish economy because many will not live in Germany permanently.
The Journal also reckons that half will not reach the tax threshold in Germany. "This means they will have more money to spend in Poland," it concludes.
You cannot divorce any of this from politics, of course. There is already a fractious debate in Germany about the costs and benefits of the migration from Turkey, which started with the invitation of "guest workers" 50 years ago.
There is a strong (though not necessarily majority) anti-immigrant sentiment. One prominent member of the Social Democrats, the central banker Thilo Sarrazin, wrote that Turks were "conquering Germany", and had "no productive function other than in the fruit and vegetable trade".
On the other hand, Economy Minister Rainer Bruederle recently said that Germany needed immigrants in order to remain competitive. Many economists and business people agree.
The Institute for Employment Research, based in Nuremberg, reckons that migration into Germany will add an extra 1.5 percentage points to the country's growth rate by 2020, with little or no effect on the rate of unemployment.
All the same, German unions fear wages being squeezed in manual work, particularly construction, where they have been negotiating minimum wages agreements.
So, your views probably do depend on where you stand. You might like cheap labour scurrying round with a broom in your kitchen - but you feel differently when it is cheap labour doing the job you thought was yours.
That seemed to be the common British experience. Will it be different in Germany?