Principle of being fair to all, with reference to a defined and recognized set of values.

There are two kinds of equity:
- Horizontal equity is the principle that says that those who are in identical or similar circumstances should pay similar amounts in taxes (or contributions) and should receive similar amounts in benefits
- Vertical equity is the principle that says that those who are in different circumstances with respect to a characteristic of concern for equity should, correspondingly, be treated differently, e.g., those with greater economic capacity to pay more, those with greater need should receive more.

European Observatory on Health Systems and Policies. Glossary. 2009.