As a contribution to the study of intradistributional mobility, this paper introduces a family of functions whose usefulness as mobility measures is justified by different theoretical results. Indeed, as a particular case, this family includes the Bartholomew index, which is widely used in the literature devoted to the dynamic analysis of personal income distribution. The paper also contains, by way of example, an application to the study of mobility in regional per capita income distribution in the European Union between 1977 and 1999.The authors wish to acknowledge the financial support from the MCYT (Project BEC2002-03941) and the Fundación BBVA
