Austronesian alignment, also known as the Philippine-type voice system or Austronesian focus system, is a typologically unusual kind of morphosyntactic alignment in which "one argument can be marked as having a special relationship to the verb". This special relationship manifests itself as a voice affix on the verb that corresponds to a noun within the same clause that is either marked for a particular grammatical case or found in a privileged structural position within the clause or both.