James Strachey's concept of the mutative interpretation is updated by contributions from Anna Freud, Paul Gray, Merton Gill, Heinz Kohut, and others. Defence analysis is challenging to analysts but such a focus has definite advantages. To be able to infer defences the analyst must tune a portion of his attention to changes in quality, quantity, or object of affect on a moment-to-moment basis. Focusing analysis around moments of feeling change that analysands can learn to recognize inside and outside the analyst's office offers them a better opportunity to be their own analyst at any moment because defences are always with us unlike parapraxes, dreams, and other observable signs of intrapsychic conflict. The building of the capacity to be one's own analyst is an important analytic goal.

some disadvantages of defence analysis are mentioned.