Socioeconomic factors are one of the main determinants of health inequalities. However, which component of socioeconomic status affects health most and how that relationship should be measured remains an open question. The aim of this study was to compare material and social deprivation indexes in order to determine which better explains health inequalities within an urban area. Following a review of the literature on small area deprivation indexes, a case study of the Italian city Genoa is presented. The city of Genoa is split into 71 small areas [urbanistic units (UU)], each of which has about 9,500 inhabitants. For each small area, socioeconomic indicators were extracted from the 2001 Census, whereas health indicators were computed from the death registry for 2001-2003. Factorial analyses was used to choose the deprivation variables, which were utilised to create two distinct deprivation indexes referring to material and social deprivation, respectively. Both deprivation indexes are positively correlated with health status proxied by standardised mortality ratios (SMRs) under 65. The material index, however, correlates more highly with SMRs than the social index, and thus the material index is the more suitable measure to explain variations in premature mortality within an urban area. Moreover, the two indexes must be kept distinct.