Having members in a not-for-profit organisation in Australia, as in many other countries, is crucial for several reasons:

1. Representation and Governance: Members often elect the committee and have a say in the leadership of the organisation. This ensures that the organisation's governance reflects the interests and values of its stakeholders.

2. Support and Engagement: Members provide crucial support in terms of volunteering, advocacy, and spreading awareness about the organisation's cause. Engaged members often contribute time, resources, and expertise, which can be invaluable for the organisation's operations.

3. Funding and Donations: Members might be donors or have connections to potential donors. Their contributions, either financially or through fundraising efforts, can significantly impact the organisation's financial stability and ability to carry out its mission.

4. Legal Requirements: Some legal structures for nonprofits in Australia, require a minimum number of members to maintain their legal status and benefits.

5. Community Building: Members form a community around the cause, fostering a sense of belonging and collective purpose. This community can provide a strong network of support and collaboration for the organisation's activities.

In essence, having members in a not-for-profit organisation in Australia is vital for its functioning, as they contribute to its governance, support base, financial stability, and overall mission fulfillment.