The design of a «pilot» questionnaire on French attitudes to uncertainty and the future is based on a dual goal. First, we endeavour to identify individual profiles based on individuals' attitudes to risk and how they perceive the future. Second, and most importantly, we set out to check whether the measured preference parameters have specific effects on the accumulation of personal wealth and demand for assets in keeping with the predictions of the savings models and to determine whether individual preference heterogeneity is, alongside the usual indicators, an important explanatory factor for wealth inequalities. Given that the thousand voluntary individuals interviewed were drawn from the sample used for the 1998 INSEE Patrimoine survey on personal wealth, we have detailed information on each interviewee's socio-demographic characteristics and personal wealth. This questionnaire contains over 80 questions covering a wide range of areas of life: consumption, leisure, health, investments, work, retirement, family, etc. Different kinds of questions are put for each area: behaviour, opinions or intentions, reactions to lotteries and hypothetical scenarios. Each question is allotted to at least one preference: attitudes to risk, time preference, short-run impatience and longer run altruism (family-related or not). The aim is to obtain an individual «score» for each preference, a mean supposed to be representative of all the responses given by the interviewee to the relevant questions. These measures are purely qualitative and ordinal: i.e. the individuals are ranked within the population based on their attitude to risk ­ rather than giving a cardinal measure of their risk aversion ­ and based on the priority they place on the present given different timescales.