I am European, always worked in Europe in many different countries, and I have pension funds scattered around all the old continent. The EU legal system does not allow pension fund transfer among countries, as far as I understand, but I also know that the pension funds I have are slowly draining due to administrative costs.
What is the best strategy to have a decent pension fund for people like me that every year or so moves to a different country?
If you're changing countries every year, investigate if you're being treated as an expat or not - the latter may allow favourable tax treatment and might allow you to keep a pension fund in one country and top it up from another one (which of course is now a lot easier as it's all Euros with very few exceptions).
Other than that you might involuntarily restrict yourself to less tax efficient savings vehicles unless you want a minuscule pension fund in each and every country.
