(I'll use whatever Web information supports my argument.) RULE 2. – PREFIXES – PARTICLES – St. Prefixes should not be considered as a separate unit. Ignore variations in spacing, punctuation or capitalization. Past practices treated prefixes and particles as separate units. The current standard matches automated systems’ filing criteria, that is, units of a name become computer program fields. Common prefixes and particles are d’, D’, Da, de, De, Del, Dela, Des, Di, Du, Fitz, la, La, le, Le, M’, Mac, Mc, O’, St., van, Van, Van de, Van der, von, Von, Von der . Alphabetize the prefix St. as though it were spelled out – Saint.