According to its own ruling, the Convention elected its President every fortnight, and the outgoing President was eligible for re-election after the lapse of a fortnight. Ordinarily, the sessions were held in the morning, but evening sessions also occurred frequently, often extending late into the night. Sometimes in exceptional circumstances, the Convention declared itself in permanent session and sat for several days without interruption. For both legislative and administrative the Convention used committees, with powers more or less widely extended and regulated by successive laws. The most famous of these committees included the Committee of Public Safety and the Committee of General Security.