While alcohol-related harm is reportedly greater on weekend evenings, research investigating trends in the intoxication levels of patrons and factors that increase risk of harm over the night is lacking.The aim was to observe trends over the course of the night for patron demographics, venue characteristics and patron intoxication.Observations of licensed venues and patrons in night-time entertainment districts of five Australian cities were conducted. In total, 798 observations occurred between 9 pm and 2 am on Friday and Saturday nights across 61 unique bars, nightclubs, and pubs. Patron characteristics such as gender and percentage of patrons under 25 years of age were estimated. Measures of venue characteristics included number of patrons, percentage venue capacity, ease of patron movement, bar crowding, and time to service. Measures of intoxication included the percentage of patrons showing any signs of alcohol intoxication, percentage of patrons too intoxicated to remain in the venue, overall level of intoxication, and percentage of patrons showing signs of drug use.Patron capacity increased across the night, peaking at 11 pm in bars, and 1 am in nightclubs. Patron intoxication measures increased for all venue types across the night. Patrons showed more signs of drug use in nightclubs than other venue types.Increasing intoxication and decreasing patron numbers later in the night provides support for restricted trading hours and improved responsible service of alcohol policies. Specific venue types should be targeted to reduce drug use in the night-time economy.