Ten years after the Department of Mayotte was created, and while the Government has made one plan after another in its favour, the situation of Mayotte remains atypical within the Republic. In sixty years, the archipelago has seen its population multiplied by 12 and it now has the highest population density in overseas France, due to both very dynamic endogenous growth and high illegal immigration. At the same time, the period following departmenthood has seen, despite real progress in the standard of living of its inhabitants, a sharp deterioration in security and quality of life conditions (transport, water, environment, housing). Crime has reached such a level that security has become the primary concern of inhabitants. In terms of education, it is also difficult to catch up, as half the population does not speak French. In the report published today, the financial courts (Court of Accounts and the Mayotte Regional Chamber of Accounts) stress that the services of the central Government and the Department of Mayotte do not manage to provide the solutions expected by the people of Mayotte on social, economic, and societal levels. In order to contribute to a strategic reflection on the sustainable development of Mayotte, the Court is making some recommendations aimed at consolidating the action of the public authorities and strengthening the fight against illegal immigration.