The demographic ageing of New Zealand society has greatly increased the proportion of the population in the older age groups along with an increasing demand for both health and social care. We report on a dynamic microsimulation model focused on two strategic areas: the impact of long-term, disabling and chronic conditions affecting older people, and their consumption of health and social care across the spectrum. The model was built on data from two New Zealand series of repeated cross-sectional surveys on health and disability respectively. We describe the construction of the model and show examples of how the model can be used to test policy-relevant scenarios for example by changing levels of disability or the balance of care and observing the impact on downstream outcomes. We conclude with assessing the potential benefits of our modelling approach and our specific model.