This chapter deals with disability discrimination law under the Equality Act. It discusses the history and background of disability discrimination law, protected characteristics, prohibited conduct on grounds of disability discrimination, and issues such as who is the comparator. The chapter also covers key debates about how the law operates and how it might be improved in the future, and deals with the economic and social models of disability. Disability can refer to a physical or mental impairment, and the definition of disability includes reference to substantial impairment and day-to-day activities. The Equality Act covers the following in relation to disability: direct discrimination (including associative and perceptive discrimination), indirect discrimination, harassment, victimisation, discrimination arising from disability, duty to make reasonable adjustments, and enquiries about disability and health.