To provide a basis for assessing the effects of large infrastructure projects on perceived environmental quality, a study was carried out in two neighborhoods adjacent to a recently built transmission line in California. Through use of a mail survey employing multiple choice, photo, and mapresponse questions, resident perceptions of neighborhood quality and transmission line visibility and effects were determined. Analysis of the responses allowed generalization about the impacts and the factors affecting them, including line distance, visibility, and mitigation measures, and whether the respondent moved to the neighborhood before or after the line's construction.