Annual membership is offered in five categories to capture the size and needs of all organisations in the resources and energy industry.
| Category | Employee Numbers | Revenue |
| Category 1 | 0 – 200 | <$10 million |
| Category 2 | 201 – 500 | <$50 million |
| Category 3 | 501 – 900 | <500 million |
| Category 4 | 901 – 1500 | <$1 billion |
| Category 5 | 1501 + | >$1 billion |
