1. A method of automatic speech recognition (‘ASR’), the method implemented with a speech recognition grammar of a multimodal application in an ASR engine, with the multimodal application operating on a multimodal device supporting multiple modes of user interaction with the multimodal application, the modes of user interaction including a voice mode and one or more non-voice modes, the multimodal application operatively coupled to the ASR engine, the method comprising: matching by the ASR engine at least one static rule of the speech recognition grammar with at least one word of a voice utterance, yielding at least one matched value, the matched value specified by the grammar to be required for processing of a dynamic rule of the grammar; and dynamically defining at run time the dynamic rule of the grammar as a new static rule in dependence upon the matched value, the dynamic rule comprising a rule that is specified by the grammar as a rule that is not to be processed by the ASR engine until after the at least one static rule has been matched.