People often get systematic and automated trading mixed up. The latter is a subset of the first. You can't have a system which is fully automated if it relies on discretionary input, no matter how small. But you can have a system which needs a human to make it run, even though there is no discretion, and its fully systematic. The main area where humans are often used with systematic trading is in execution. It's relatively common for people to create software that analyses prices and produces a trade, which the person then has to execute. (At the large hedge fund I used to work for, we used a mixture of automated execution algos, and real people to execute trades. FWIW the best humans were better than the best algos, on certain kinds of markets) This post isn't for you. It's only for those who want to automate their execution as well. This is the fourth post in a series giving pointers on the nuts and bolts of building systematic trading systems. You may also want to look at my post on building a simple execution algo, which I'll refer to occasionally here. The rest of this, due to ET's 10K character limit on posts, can be found on my blog (I just checked the link works!) GAT PS I can't see any messages from trolls, so only respond if you enjoy talking to yourself. Read my policy on trolls, here