This paper continues an ongoing investigation of the social and economic 'segregation' of students between schools in England, and of the likely causes of the levels of and changes over time in that segregation. The data presented here come from a re-analysis of the intakes to all schools in England 1989-2011 as portrayed by the official returns to the Annual Schools Census. Using a segregation index it shows how strongly clustered the students are in particular schools in terms of six indicators of potential disadvantagerepresenting poverty, learning difficulties, first language and ethnicity. It shows again, and with further years than previously, that each indicator has its own level and pattern of change over time. This suggests that there is not just one process of segregation. However, the patterns for primary-age schools (5-10) are exactly the same for most indicators as the patterns for secondary-age schools (11-18). These two findings in combination rule out a large number of potential explanations either for changes in or levels of segregation-including volatility of small numbers, and recent changes in the types of schools and in the ways in which school places are allocated. Instead, based on correlations with other indicators of population, school numbers, and the economy, a new set of determinants are proposed. The long-term underlying level of segregation appears to be the outcome of structural and geographic factors. However, the annual changes in segregation for most indicators can be explained most simply by changes in the prevalence of each indicator. For example, the UK policy of inclusion has considerably increased the number of students with statements of special needs in mainstream schools, and this has resulted, intentionally, in less segregation in terms of this indicator. Segregation by poverty, however, requires something further to explain changes over time, and this is provided at least partly by changes in GDP over time, and partly as a one-off impact of increased parental choice. Some of these factors, such as the global economy or the prevalence of specific ethnic minority groups, are not directly under policy-makers' control. This means that it is the more malleable factors leading to the underlying levels of poverty segregation that should be addressed by any state wanting a fair and mixed national school system. In England, these controllable factors include the use of proximity to decide contested places at schools, and the continued existence of faith-based and selective schools. The implications are spelt out. This paper considers the pupil intakes to Academies in England, and their attainment, based on a re-analysis of figures from the Annual Schools Census 1989 to 2012, the Department for Education School Performance Tables 2004 to 2012, and the National Pupil Database. It looks at the national picture, and the situation for local education authorities, and also examines in more detail the trajectories of the three original Academies. It confirms earlier studies in finding ...