This thesis concerns the modelling of individuals’ health over the life course, within the framework set by the now substantial international literature on the relationship between socioeconomic status and health. The focus is on people with long term illnesses and related disabilities, on inequalities in health by socioeconomic status (SES) and on the impact of health on employment. ¶ The main tool of analysis is a dynamic microsimulation model of the Australian population which tracks the demographic, socioeconomic and financial characteristics of individuals and their families over the life course. Its original form, developed at the National Centre for Socioeconomic Modelling, University of Canberra, is based on a one per cent representative sample of the Australian population (around 150,000 individuals), with a series of life course events simulated for individuals and their families up to 2050 - such as births, deaths, migration, taxes, education, labour force participation, earned income, wealth accumulation and government transfers. ...