May 4 - McCann family members and British media criticise local police for what they call a slow initial response, failure to notify ports and borders in time, and failure to secure the crime scene, which may have led to vital clues being lost.
Police say that under Portuguese secrecy laws they are unable to reveal details of the investigation.
May 5 - Police say they have put together a sketch of a suspect and that they believe Madeleine is still alive and being held within three miles of the crime scene. Media reports say the sketch is vague and only features the back of a man's head.
May 8 - Police say they have investigated 350 suspicious incidents but still have no idea where she might be. Portuguese newspaper Correio de Manha says Madeleine may have been kidnapped by a paedophile ring.
May 11 - Scottish businessman Stephen Winyard offers a 1 million pound ($2 million) reward. Former England soccer captain David Beckham makes televised appeal for information.
May 12 - Madeleine turns four.
May 13 - Virgin boss Richard Branson, author J.K. Rowling and footballer Wayne Rooney are among those to have contributed to rewards now totalling 2.5 million pounds.
May 13 - Half a million pilgrims attending the 90th anniversary of the first appearance of the Virgin Mary at the Sanctuary of Fatima pray for Madeleine's return.
May 14 - Police search a villa just up the road from where Madeleine was snatched and take a British man, Robert Murat, to a police station for questioning. He is later released.
May 30 - McCanns meet Pope Benedict during a general audience at the Vatican.
June 1-10 - The couple travel to Spain, Germany, Netherlands and Morocco appealing for help to find their daughter.
Aug. 7 - Traces of blood were found on the wall of the apartment where Madeleine went missing.
Aug. 11 - Portuguese police Chief Inspector Olegario Sousa tells the BBC that Madeleine may be dead.
Aug. 31 - McCanns say they have instructed their lawyers to begin legal action against Portuguese newspaper Tal & Qual after it claimed police believe the couple killed Madeleine.
Sept. 6 - Kate McCann spends 11 hours being questioned as a witness by police.
Sept. 7 - Parents to be formally declared as suspects.