In accordance with the present invention, a method for increasing both dialect precision and usability in speech recognition and text-to-speech systems is described. The invention generates non-linear (i.e. encoded)baseform representations for words and phrases from a pronunciation lexicon. The baseform representations are encoded to incorporate both pronunciation variations and dialectal variations. The encoded baseform representations may be later expanded (i.e. decoded) into one or more linear dialect specific baseform representations, utilizing a set of dialect specific phonological rules. The method comprises the steps of: constructing an encoded pronunciation lexicon having a plurality of encoded and unencoded baseforms; inputting one or more user specified dialects; selecting dialect specific phonological rules from a rule set database; and decoding the encoded pronunciation lexicon using the dialect specific phonological rules to yield a dialect specific decoded pronunciation lexicon.