The soundex system is an indexing system based on the way a name sounds rather than the way it's spelled used to find individuals in census records. However since soundex is based on English pronunciation, some European names may not soundex correctly. An example is the French name Roux - where the x is silent. While Rue (R000) is pronounced identically to Roux (R200), they will have different soundex codes. This could be true of any surname that does not use English pronunciation.
For the purpose of genealogy what Kelly has been working on has an application. He has laid the ground work for Francophone to English soundex mapping. But it would still take a software coder to make this into something that could be easily used by the masses.
