I've noticed a few threads on this topic and it truly aroused my curiosity as I always presumed these sort of strategies were exclusive to High Frequency Traders. Here are some amateur questions that I have regarding this matter: 1) What exactly is rebate trading and how does one 'add liquidity'? Does it involve posting bids/ offers via any ECN of your choice (ex: BATS or EDGE A)? 2) Where can I learn more about this strategy (books, links or any other resources will be much appreciated)? 3) Is this sort of strategy still prominent or sustainable considering the proliferation of HFT? Thanks a lot for taking the time to answer these questions. Of course, I did do a thorough search and didn't get too far, hence I decided to ask here.