I admit that my knowledge of economics is limited, so I am ready to be corrected by some of the economic experts here on the board.
I think some of the factors that are helpful for a country to achieve a low unemployment rate are a flexible job market, positive conditions for smaller and bigger businesses, which gives them an incentive to invest (e.g. acceptable tax rates, not too much regulation, a sufficient number of available skilled employees) and a diversified economy. These factors certainly play a role in Switzerland's economic success, which is reflected by the relatively low unemployment figures.
