Drilling is the idea that techniques should be practiced repetitively in their ideal form on usually a cooperative partner offering no resistance. This allows your to quickly build the coordination and muscle memory (or procedural memory, back brain familiarity, etc.) of the technique so that when done in a live context such as sparring, you don't need to take a great deal of time thinking your way through the technique or performing awkwardly and in uncoordinated fashion.

Drilling can also be viewed as a spectrum along which completely cooperative practice is on one end and where sparring against a fully resistive opponent is on the other. Even if the opponent is resisting, if their ultimate goal is to cooperate with you to learn the technique for yourself, this is viewed as some form of drilling as opposed to sparring. This gray area can also be referred to as "semi-live" training, positional sparring, or "ecological" training. The goal of semi-live training is to allow you to respond to your opponent's attempts to defend or counter your technique while still leaving the attempt controlled enough to guarantee success.

"Uchikomi", the repetitive practice of entries to a throw in Judo, is a form of drilling.

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