On FSAirlines you can have an unlimited number of partnerships with other airlines. Having a partnership does not only show others that these two airlines try to work together, but you can also set up codeshare flights with a partner airline.
Request a new partnership
On the Partnerships page you can request a new partnership. Until the request is accepted by the other airline the partner airline is shown red on the list of partner airlines on the overview page and you aren't able to offer/add any codeshare flights.
Accept a new partnership
If another airline requests a new partnership with your airline you will get a notification message and can accept the partnership on either the overview or the partnerships page.
Decline a partnership
Both parties can decline a partnership any time they want, it doesn't matter if the partnership has already been accepted or not.
You can set up codeshare flights with a partner airline. You will get a 10% bonus on passengers on these flights.
If you're flying the same routes as your partner airline you will get 10% passenger deduction on these flights.