A method of automatic speech recognition, the method comprising the steps of receiving a speech signal, dividing the speech signal into time windows, for each time window, determining acoustic parameters of the speech signal within that window, and identifying speech features from the acoustic parameters, such that a sequence of speech features are generated for the speech signal, separating the sequence of speech features into a sequence of phonological segments, and comparing the sequential phonological segments to a stored lexicon to identify one or more words in the speech signal.