Investigation of the factors affecting individual response to noise provides an improved basis for the selection and implementation of noise impact reduction policies. This investigation is necessary because the cause and effect relationship between the level of noise exposure and noise response is confounded by personal and situational variables. Examination of the effects of these variables on response to road traffic noise with the use of data collected at residential sites in Southern Ontario suggests the following points for residential planning decisions. Arguments for taking no action to reduce noise impact are not supported. The sex, age, and socioeconomic compositions of residential areas are not important considerations for implementing measures to reduce noise impact. Life-style characteristics of residents on the other hand do affect response to noise. Methods to reduce noise must be effective indoors and outdoors to have a significant effect on attitudes: air conditioning alone is inadequate. Noise barriers appear to be more effective for improving attitudes than their noise reduction properties would suggest.