Journal article: The Turkish labour market, like that of many developing economies, is characterised by widespread recourse to informal jobs. Several measures have recently been taken by the Turkish authorities to limit the extent of this tendency. These are in keeping with the dynamic process of accession to the EU to wich Turkey has been commited since the opening of negotiations in October 2005. From Household Labour Force surveys conducted by the Turkish Statistical Institue, the study presented here depicts a panorama of informal employment in Turkey before the implementation of these measures. It responds to the need expressed by the Council of the European Union to hve an analysis of underclared work. From a desciptive analysis of the main features of informal jobs and from the estimation of the probability of informal employment, it brings out a number of lessons on how to target policies to combat informal employment in Turkey and on the people who encounter the greatest difficulties in accessing or participating in the market.