# AOP vs BOI
Both are categories of 'person' under Section 2(31), but they differ in who can be a member and why they are formed.
## Association of Persons (AOP)
- A group formed for a shared goal or business — individuals working together for joint income.
- Formed voluntarily with a common purpose.
## Body of Individuals (BOI)
- Individuals (e.g. trustees, executors) who receive income jointly for a common benefit.
- Generally lacks the voluntary association that characterises an AOP.
## Comparison
| Criteria | AOP | BOI |
|---|---|---|
| Membership | Can include individuals AND entities (companies, firms, etc.) | Only individuals can be members |
| Formation purpose | Formed voluntarily with a common purpose/goal | No requirement of a shared purpose or intention |
> Memory hook: BOI = Bodies of individuals only; AOP can mix individuals and other persons.