Response to treatment of late-life generalized anxiety disorder has been defined by a variety of methods, all based on statistically significant reductions in symptom severity. However, it is unknown whether these improvements in symptom severity are associated with meaningful differences in everyday functioning. The current study used four methods to define response to treatment for 115 primary-care patients 60 years and older, with a principal or coprincipal diagnosis of generalized anxiety disorder. The methods examined included percentage of improvement, reliable change index, and minimal clinically significant differences. Agreement among classification methods and their associations with general and mental health-related quality of life were assessed. Results indicated moderate agreement among symptom-based classification methods and significant associations with measures of quality of life.