Crop rotation (that old chestnut)

I take the view, which may be somewhat controversial, that crop rotation began with farmers with four fields, where it worked very efficiently. On a small scale, it certainly makes sense to grow nitrogen-fixing plants before plants which have a high nitrogen requirement, but as for controlling the spread of pests and so on, these can unfortunately be pretty mobile - even the soil-borne type. Having said that, I do still rotate, and it's certainly better than not rotating!