Markets change so do countries is it safe …

Investing overseas is safe …

…as long as you know what you're doing and understand the basics, i.e. if you expect to get a higher return by investing overseas (either in capital growth or rental yield) then you must be prepared to take a higher risk.

Conduct lots of research both in terms of properties but also regarding the country/market you're planning to invest in, one good place to start is: http://www.globalpropertyguide.com 

Don't buy overseas if you don't have access to a decent property manager and obviously you need good quality legal/finance/accounting support. Also think about how you will repatriate your income/capital gains and do whatever you can to minimize your tax before you buy.

I think the current US market with so many foreclosures provides excellent opportunities if you have the time / contacts to source premium property in  well established markets e.g. certain parts of florida. At the same time I would stay well away from the widely publicised areas of upstate New York and Buffalo areas even though they have rental yields of 20% and above – those yields are for a reason !! and those reasons make it very hard to manage those investments from overseas.

I also think that certain European markets will soon become attractive again e.g. certain areas of London that are up of urban renewal could be a good investment with the UK market having dropped and still dropping, low interest rates and a cheap british pound.

Most Asian markets I would now avoid until we see the full effect of the dramatic drop in exports to the US, also in quite a few asian markets investors have to setup legal structures to hold control over real estate as foreigners are not  allowed to directly own real estate. Something that can be done if you know the market, but personally I want to have a titled property in the name of an entity I can control 100%.

Another risk of overseas investing can be currency risks, which can be huge and wipe out years of capital gains in the space of a few weeks or months. I know …  … and learned an expensive lesson.

And maybe the most important point, if things go wrong or you have made an expensive mistake, cut your losses and get out if necessary. It's a classic mistake beginning investors make, holding on to losers in the hope they will recover and selling winners. That way you limit your upside and expose yourself to downside.