&gt; None of which we get from HFT.<p>No but we do get it from market makers.  HFT has led to a dramatic decrease in the price of market making.  Unless your claim is that market making is not something that should be allowed?<p>&gt; And risk management? Please. They&#x27;re only managing their own risks.<p>My point about risk management was about the aggregate benefits of the markets, not about HFT providing someone risk management.  If you have some risk that you want to sell, there will be a buyer for it because of the aggregate sum total of all the zero sum transactions available in the markets.