Recently flew domestically into SYD and had to transfer to an overseas flight. It is inconceivable to me that going from one terminal to another could be so inefficient and costly. There is no tram that runs between domestic and international terminals. Option #1 is a shuttle bus (called T Bus) that runs every 30 minutes (and not on a schedule). Passengers were queued up for this service and it isn't even free - there is a A$5.50 charge for what amounts to an inferior unreliable service. Option #2 is a city train (called Airport link) which also charges A$5 for transport between terminals. Option #3 is a taxi which we chose because of a reasonably tight connection. Fare was A$15 and after generous tip cost me A$20. I cannot think of another major airport in the world that does not offer high quality reliable comfortable free transport between terminals. Sydney should be ashamed of this and it is a clear disincentive to use SYD to change planes from domestic to international flights.