The date of the National day is traditionally determined by the reigning Prince. The previous Princes often chose the day of the saint they were named after. For instance the late Prince Rainier III chose 19 November, the day that celebrates St. Rainier. When Prince Albert IIascended the throne he ended this tradition by choosing the same day as his father, instead of the day of St. Albert, 15 November. The 19 November also happens to be the same day of Albert II's official ascension to the throne.
The people of Monaco may celebrate by displaying the Monegasque flag.
It is an opportunity to see the pomp and circumstance of the Principality. Knights of Malta, distinguished ambassadors, consuls and state officials wear medal-laden uniforms as they congregate in the Saint Nicholas Cathedral after the mass. The Princely Family of Monaco is expected to show up on national day. The birth of Albert II's children has been celebrated in a similar fashion as a national day.