This paper presents a general survey of the Swiss economy. It emphasises the various factors that have been put forward to explain the very low unemployment rate recorded in Switzerland up to the beginning of the 1990s. It also analyses the factors which may be held responsible for the dramatic reversal of the Swiss labour market situation, by considering the modification in the employers' and workers' behaviour in Switzerland as well as the changes observed in the structure of the foreign labour force. It comes to the conclusion that the unemployment observed since 1991 is not simply a consequence of a deterioration in the functioning of the Swiss labour market compared with earlier periods, but rather a result of changes in immigration policies and also the reflection in the statistics of a truer picture of the labour market imbalance created by the restructuring of the economy.