Gamma hedging is a strategy that tries to maintain a constant delta in an options position. This is done by buying and selling options in such a way as to offset each other, resulting in a net gamma of just around zero. At such a point, the position is said to be gamma-neutral. Often, a trader will want to maintain zero gamma around a delta-neutral (zero-delta) position as well. This is done via delta-gamma hedging, where both net delta and net gamma are close to zero. In such a case, an options position's value is immunized against price changes in the underlying asset.