Madeleine McCann disappeared on the evening of Thursday, 3 May 2007. She was on holiday with her parents and twin siblings in the Algarve region of Portugal. The British girl went missing from an apartment located in the central area of the resort of Praia da Luz, a few days before her fourth birthday, and has still not been found.
Madeleine's parents, Kate and Gerry McCann, have said that they left the children unsupervised in a ground floor bedroom (4) while they ate at a restaurant (1) about 50 metres away.

The initial investigation by the Polícia Judiciária (PJ), the Portuguese criminal investigation police, was based on the assumption that the child had been abducted. After further investigation, the PJ stated that there was a strong hypothesis that she might have died in her room. During the investigation there were a number of unconfirmed sightings of Madeleine in Portugal and elsewhere, and additional scientific evidence was obtained. The investigation involved the co-operation of the British and Portuguese police and demonstrated the differing methodologies employed by each, with regard to such aspects as the amount of information released to the public and the legal status of those involved in the case.

Robert Murat, a local resident, was given arguido or suspect status on 15 May 2007. Kate and Gerry McCann were also named as arguidos on 7 September but were allowed to fly back to the United Kingdom on 9 September. As investigators failed to find evidence of any wrongdoing, all three suspects had their arguido status lifted on 21 July 2008. The Portuguese Attorney General archived the case, also on 21 July, adding that the case could be reopened if new evidence emerges.
The disappearance and its aftermath were notable for the breadth and longevity of the media coverage. This was initially due to the active involvement of the parents in publicising the case and to several awareness-raising campaigns by international celebrities and, latterly, to the interest that arose from the parents being named as suspects. The event generated international media attention with controversy surrounding the Portuguese-led police investigation and the actions of Madeleine's parents. There has also been criticism of the extent and nature of the publicity and of the reporting of the disappearance in both the Portuguese and British media.