Big Brother (Australian season 7)
Big Brother Australia 2007, also known as Big Brother 7, was the seventh season of the Australian reality television series "Big Brother". Episodes were broadcast on Network Ten in Australia, and the first episode aired on 22 April 2007. 
Despite a drop in ratings compared to previous series, and a number of controversies, the then "Big Brother" executive producer Kris Noble considers the year's series a success. At the end of this season's finale broadcast 30 July 2007, it was announced by host Gretel Killeen that "Big Brother" would be returning for an eighth season in 2008. In the finale Aleisha Cowcher was announced winner of "Big Brother Australia 2007". She won by the closest winning margin ever in the Australian series. The news the following day reported a margin of 51% versus 49% – a difference of 65 votes. This was the last season hosted by Gretel Killeen.
List of Big Brother (Australian TV series) season 7 housemates
During the first week of the season, 15 housemates were added to the house. 12 went into the house on opening night while viewers could vote in two extra housemates, one male and one female from a group of six. The following night, Susannah and Zoran entered the house along with an extra housemate, Billy who is added to put Hayley and Andrew's secret relationship challenge into jeopardy. On Day 11, Demet entered the house after being voted in by the existing housemates. Nick entered the house on Day 18 as the winner of the Starburst Golden Key promotion. A further two female housemates, Daniela and Laura, later entered as "Intruders" on Day 31. Two further Intruders Michelle and Zach, entered on Day 50. On Day 84, a Celebrity guest known officially as a Housemate: Kyle Sandilands entered the house with a mission from Big Brother. The total number of housemates to enter the house is 24.