How can we measure an individual's identity? We can ask someone to talk about their vision of their own identity and who they feel they are. Or we can ask them to fill out surveys and track over time how the different ways that people describe themselves change. The former approach lends itself more to qualitative analysis while the latter often relies on quantitative measurement. These measurements are gathered for a sample of the population that allows researchers to track identity changes over time. Often criticised as blunt instruments of social investigation, aggregate indicators of identity, and the measures used to extract such data, provide a picture of changing patterns of attachment and belonging within a population. Quantitative measures not only allow us to track changes in identity within a population, but also allow us to compare identity patterns in one nation and another. What such measures miss, however, is the more personal aspect of identity. If these measures provide an incomplete vision of identity for any one individual, in the aggregate they prove quite useful. This article examines the contribution of quantitative data to the meaning of national identity in Scotland and Quebec. It explores the different approaches to quantitative identity measurement and highlights questions raised by the research. It then turns to the civic-ethnic debate to determine what light quantitative measures shed on identity, and the extent to which distinctions between civic and ethnic national identity contribute to a greater understanding of national identity in Scotland and Quebec. The article suggests that the distinction between civic and ethnic identity is not as clear as we might assume and that the key difference between the two cases is not the content of identity - what individuals think it means to be Scottish or Quebecois - the salience of identity in political debate. Analyses of identity and its measurement allow us to better understand the way that individuals define themselves and the extent to which they feel themselves as part of a collective. This in itself is of academic interest but equally important is an assessment of the ways that individuals identify their own political community. We know, at present, that individuals are participating less in formal avenues of political activity; we know that efficacy, trust and satisfaction with politics and politicians are low. We know that individuals feel disengaged from their fellow citizens and their political system. When asked to explain their identities individuals very rarely mention their role as citizens. However, we also know that attachment to sub-national entities remains strong. Individuals identify with their sub-state national unit in a way that they do not identify with the State. Understanding why individuals identify with the nation, and the extent to which they do so, helps political scientists better to understand the views of individuals towards the State and their fellow citizens. Identity measurement in Scotland and Quebec Part of the problem of measurement stems from the moving 'target' of identity. The importance and substance of identity vary both in context and over time. Within the literature, identity has been used as a sense of belonging (Tajfel 1982; Wetherell 1996b), a particular outlook (Erikson 1974) or a self-ascribed label (Hall 1996). Recent efforts to problematise identity highlight the frustration with existing measurement attempts (Mendelsohn 1999; McCrone et al. 1998). Criticism addresses issues of definition and measurement, such as the construction of identity scales (Mendelsohn 1999), the operationalisation of identity theory (Hall 1996), and the treatment of identity data in the search for meaningful correlations. In particular, researchers point to the low salience of political beliefs and the disputed relationship between attitudes, values, beliefs and behaviour. Each of these, when compounded by the questionable ability of individuals to explain their own identities, proves a stumbling block for any empiricist attempting to capture the true meaning of national identity Aggregate measures of identity in Scotland find little consistency prior to the introduction of the Moreno question in 1986 (Moreno 1988). …