Here is a timeline of the key events since Madeleine McCann's disappearance.
2007
May 3 - Kate and Gerry McCann, from Rothley, Leicestershire, leave their three children asleep in their holiday apartment in Praia da Luz while they dine with friends at a nearby tapas restaurant.
Nothing is amiss when Mr McCann checks on the youngsters at just after 9pm, but when his wife goes back at about 10pm she finds three-year-old Madeleine missing.
Jane Tanner, one of the friends eating with the McCanns, later reports seeing a man carrying a child away earlier that night.
May 5 - Portuguese police reveal they believe Madeleine was abducted but is still alive and in Portugal, and say they have a sketch of a suspect.
May 14 - Detectives take Anglo-Portuguese man Robert Murat in for questioning and make him an "arguido", or official suspect.
Officers also search the home he shares with his mother in Praia Da Luz, just 100 yards from where the youngster was snatched.
May 25 -Detectives finally release the description of the man reported by Jane Tanner three weeks earlier following pressure from the McCanns, their legal team and the British Government.
May 30 - Mr and Mrs McCann meet the Pope in Rome in the first of a series of trips around Europe and beyond to highlight the search for their daughter.
August 6 - A Portuguese newspaper reports that British sniffer dogs have found traces of blood on a wall in the McCanns' holiday apartment.
August 11 - Exactly 100 days after Madeleine disappeared, investigating officers publicly acknowledge for the first time that she could be dead.
August 31 - The McCanns launch a libel action against newspaper Tal & Qual over a front-page story which claimed police believe they killed their daughter.
September 7 - During further questioning of Mr and Mrs McCann, detectives make them both "arguidos" in their daughter's disappearance.
September 9 - The McCanns fly back to England with their two-year-old twins Sean and Amelie.
September 11 - Portuguese police hand the papers in the case to the public prosecutor, Jose Cunha de Magalhaes e Meneses, for him to decide whether to bring charges against anyone.
October 2 - Goncalo Amaral, the detective in charge of the inquiry, is removed from the case after criticising the British police in a Portuguese newspaper interview.
October 9 -The case is taken over by Paulo Rebelo, a senior detective with Portugal's investigative Policia Judiciaria normally based in Lisbon.
October 25 - The McCanns release a new artist's impression drawn by an FBI-trained expert showing the man described by Jane Tanner.
November 1 - Mr McCann returns to work as a consultant cardiologist at Leicester's Glenfield Hospital.
November 22 - Portugal's attorney general, Fernando Jose Pinto Monteiro, says the huge publicity surrounding Madeleine's disappearance could have resulted in her kidnapper killing her.
November 29 - Forensic experts from the UK and Portugal meet at Leicestershire Police headquarters to discuss DNA samples collected during the inquiry.
December 22 - Mr and Mrs McCann send a public message to their daughter, telling her: "Our only Christmas wish is for you to be back with us again."
2008
January 9 - Mr McCann plays down speculation they may approve a movie about Madeleine's disappearance after their spokesman meets the IMG agency, the firm behind the award-winning drama-documentary Touching The Void.
January 20 - The McCanns release police artist sketches, based on a statement given by a British holidaymaker, of a man they believe may have abducted Madeleine.
February 4 - Portugal's top detective, Alipio Ribeiro, says in a radio interview that police were "hasty" in making Madeleine's parents suspects in her disappearance.
February 13 - Portuguese justice minister Alberto Costa says the police investigation into the young girl's disappearance is nearing its end.
March 19 - Mr and Mrs McCann accept £550,000 libel damages and front-page apologies from Express Newspapers over allegations they were responsible for Madeleine's death.
March 20 - Portuguese police return three computers and other seized possessions to Mr Murat.
April 7 - Three Portuguese detectives, led by Mr Rebelo, fly to Britain to reinterview the seven friends on holiday with the McCanns when Madeleine vanished.
April 10 - Speaking in Brussels, Mr and Mrs McCann call for a Europe-wide missing child alert system.
But this is overshadowed by a leak of the couple's first police interviews, which reveals that Madeleine asked her mother on the morning before she vanished: "Mummy, why didn't you come when we were crying last night?"
April 13 - Solicitors Simons Muirhead and Burton, acting for Mr Murat, confirm he is suing 11 British newspapers and one TV station for libel.
April 26 - In an interview for a BBC Radio 4 documentary, Mr McCann says he believes his daughter is still "probably alive" and that there is "absolutely zero" evidence to suggest otherwise.
April 30 - An ITV documentary reveals that the McCanns almost decided against leaving their children behind when they went out on the night Madeleine disappeared.