Rather than using family names, as is the usual custom in most Western nations, Icelanders carry patronymic or matronymic surnames, patronyms being far more commonly practised. Patronymic last names are based on the first name of the father, while matronymic names are based on the first name of the mother. These follow the person's given name, e.g. ''Elísabet Jónsdóttir'' ("Elísabet, Jón's daughter" (Jón, being the father)) or ''Ólafur Katrínarson'' ("Ólafur, Katrín's son" (Katrín being the mother)). Consequently, Icelanders refer to one another by their given name, and the Icelandic telephone directory is listed alphabetically by the first name rather than by surname. All new names must be approved by the Icelandic Naming Committee.