What is the financially best and most efficient way to invest a sum of approx. €150K for a relatively short term (approx. 10-20 years). IMHO, State Savings Certs & and Prize Bonds appear to be the safest option and stock markets look to be at their highest. In summery: Prize Bonds = Chance to win prizes every week, while able to recoup initial investment. State Savings = Probably safest, but relatively poor interest rates. Stock Market = Appears to be booming ATM so maybe not best time to invest. Apologies for repeating the same old chestnut, but it's probably a grand question for long term lurkers and fantasists to kick around.