Study on the extension of and prices at the informal irregular labour market: e.g. legitimate activities, often renumerated, that take place ouside normal labour contracts and without proper administrative procedures. R'.s perception of changes at the labour market with respect to preferred number of 'regular' working hours, need for jobs on the side, sufficiency of incomes, acceptance of less suitable work, volunteerwork / r'.s wish for informal side lines, moonlighting, motives / attitude to illegal side lines, making use of moonlighters, type of work done, frequency, price per hour, way of payment, receipt / motives for doing work on the illegal informal labour market, type of work, frequency, earnings per hour / legal additional side lines: type of work, frequency, earnings per hour. Background variables: basic characteristics/ residence/ housing situation/ household characteristics/ occupation/employment/ income/capital assets/ education