Recent research has highlighted significant inequalities in mortality and life expectancy by socio-economic group; differences that have come further under the spotlight during the Covid-19 pandemic. In this webinar, we will discuss how cause-of-death data from the Office for National Statistics can help us to understand how inequalities arise at the all-cause level. The key to understanding mortality inequality is to think about the chain that connects risk factors, relative risks, and cause-of-death mortality through to all-cause mortality. Mortality inequalities arise when the prevalence of specific risk factors varies significantly between geographical and socio-economic groups and where these risk factors have high relative risk associated with specific causes of death. Risk factors that can be considered to be controllable by the individual (e.g. smoking) rather than preventable (e.g. Human Papilloma Virus) or not preventable (e.g. genetic variations) are much more likely to be associated with mortality inequality. We will discuss how cause-of-death mortality varies by region and deprivation group and also by Clinical Commissioning Group (CCG) across England. And, with reference to specific causes, we will gain insights into how specific risk factors vary between groups and through time alongside other factors such as medical advances. We will conclude with some discussion of the potentially disruptive effect of Covid-19 on cause-of-death data.