The rate of change for delta with respect to the underlying asset's price. Gamma is an important measure of the convexity of a derivative's value, in relation to the underlying. In a delta-hedge strategy, gamma is sought to be reduced in order to maintain a hedge over a wider price range. A consequence of reducing gamma, however, is that alpha too will be reduced.

Mathematically, gamma is the first derivative of delta and is used when trying to gauge the price movement of an option, relative to the amount it is in or out of the money. When the option being measured is deep in or out of the money, gamma is small. When the option is near or at the money, gamma is at its largest. Gamma calculations are most accurate for small changes in the price of the underlying asset.