For randomly chosen residents of the Minneapolis-St. Paul, Minnesota, metropolitan area, survey responses, reported bites, and observed defensive behaviors (e.g., brushing, swatting) for a 5-min period in their yard were compared with simultaneous mosquito counts from a human-baited drop-net trap 6 m from the resident. When mosquitoes trapped, reported bites, or observed behaviors per 5 min were 3 or more, the majority of respondents described the mosquito levels as greater than "moderate" and anticipated reduced outdoor time and/or possible repellent use. At 25 or more mosquitoes trapped, 11 or more reported bites, or 16 or more observed behaviors per 5 min, response was "bad", with most people anticipating a major reduction in outdoor time (without repellent), "probably" or "definitely" planning to use repellent, and anticipating some outdoor time loss even if using repellent. Levels of less than 3 mosquitoes trapped per 5 min were related to moderate annoyance in 20-45% of the population. Individual response was highly variable, and the personal and environmental covariates measured did not account for more than half the variability.