To assess the prevalence of alcohol misuse in the night-time economy. A random sample of 893 people were interviewed and breathalysed in 24 repeated, cross-sectional surveys over the course of a year in the city centre streets of a European capital city between 11.00 pm and 3.00 am. Median blood alcohol concentration (BAC) in men was 0.13% (min = 0%, max = 0.33%) and in women was 0.09% (min = 0%, max = 0.27%)-which were below the threshold used to indicate 'at risk BAC' (0.15%; for men t = 9.32, P < 0.001 and for women t = 17.54, P < 0.001). Men provided higher BACs than women (t = 7.17, P < 0.001). The relationship between age and BAC for men described an inverted 'u', peaking at 29 years, but for women the relationship was positive and linear. BAC was inversely related to the ability to remember and report the evening's consumption (z = 4.76, P < 0.001). Reported consumption predicted only 12% (P < 0.001) of the variance in BAC for men and 10% (P < 0.001) for women. 'At risk' intoxication was apparent only in a minority of drinkers, who were mostly employed men in their late twenties, but a third of men and half of women had consumed more than the recommended daily limit. The probability for respondents to recall past consumption diminished as BAC increased suggesting self-report data are not suitable to assess consumption in heavy drinkers. Breath analysis surveys are valuable in understanding alcohol misuse in the night-time economy.