The Australian migration system has a number of different partner visas. All of the partner visas are in two stages. First, the visa applicant must apply for a temporary partner visa and then a permanent partner visa.
All partner visa applicants must be sponsored by their Spouse (the person they are married to) or a De Facto Partner. The sponsoring Spouse or De Facto Partner must be an Australian or eligible New Zealand citizen or an Australian Permanent Resident.
On 9 December 2017, Australian marriage laws were passed to allow for marriage equality, allowing two people, regardless of their gender identity, to marry. Thankfully, the changes in the law have meant that all partner visa options are now available to same sex couples. Under the old laws, same sex couples were prohibited from applying for some classes of partner visa.
In all cases, regardless of if the couple is married or in a de facto relationship, same sex or opposite sex, they must be able to prove to the Immigration Department that they have a genuine and continuing relations before the visa will be granted or approved.