I am a young academic from The Netherlands presently working in Sweden. Due to the nature of modern Academia, I expect that within the next 40+ years, I will be working in many different countries around the world. I would like to not worry about my pension, but given the discrepancy between the design of many pension funds (working in same country, even at same employer, for decades) and the expected nature of my work/academia career, I probably should.
Note: the following two paragraphs are of speculative nature and do most likely not represent an accurate description of the future!
We jump to the year 2060. To combat problems caused by an aging population, rising health-care costs and a generally poor economic situation due to an increasing pressure on increasingly smaller resources, most governments around the world have risen the pension age to 75 years, and so has the one where I work. Finally I have reached by 75th birthday and I can rest.
In the past 50 years of work, I have worked in 10 different countries, including Sweden, USA, China, and Brazil. Through my life, there are two jobs I have held 10+ years. All others were temporary positions lasting between 2 and 5 years. Now pension money starts flowing into my bank account.
Or does it? Is the sum of ten small pensions equally good as one large one? Will a country I left 40 years ago even remember me — or how do I make sure they do? Should I have taken care of this when I was young and make private arrangements — or are there international agreements taking care of this situation? Honestly, I don't even know where to start and what questions to ask. 2060 — or even 2050 — is a very long time away.
I found a related question: Wandering EU worker: Pension / retirement fund if working in multiple countries?. This question is slightly different, has received limited attention, and I don't understand the answer: investigate if you're being treated as an expat or not (what does this mean? Isn't an expat just a synonym for a labour migrant?), you might involuntarily restrict yourself to less tax efficient savings vehicles (what is a savings vehicle?), and what is a second pillar as mentioned in a comment?
Where and how do I start thinking about organising funds for my old day if I expect to live and work in many different countries?