A method of speech recognition in a speech recognition system comprising a user profile database, a decoder module, an acoustic model selection module, a language model and lexicon module for providing a catalogue of words and a statistical model reflecting probabilities of sequences of words within a language, a grammar module for providing grammar rules associated with a language, and a pronunciation guesser module for setting rules for pronunciation generation of a language, wherein the language model and lexicon module receives data from the pronunciation guesser module, the method comprising: establishing a user profile of a user having language skills in the user profile database, the language skills determined based on personal data of the user; configuring the acoustic model selection module to select a plurality of acoustic models from a list of acoustic models, the plurality of acoustic models selected from the list including a first language, a first degree of proficiency, a second language, and a second degree of proficiency from the user profile of the user; employing, at the decoder module, a first acoustic model corresponding to the first language and the first degree of proficiency of the user, and a second acoustic model corresponding to the second language and the second degree of proficiency of the user based on the language skills included in the user profile of the user, the language skills indicating languages spoken by the user and, for each language spoken by the user, a degree of proficiency; and performing speech recognition at the decoder module on speech data representing speech by the user speaking in the first language using the first acoustic model, and, switching from the first acoustic model to the second acoustic model being triggered based on automatic identification of the user switching from speaking in the first language to the second language, causing the decoder module to perform speech recognition using the second acoustic model, wherein the decoder module interacts with the language model and lexicon module and the grammar module to perform the speech recognition. establishing a user profile of a user having language skills in the user profile database, the language skills determined based on personal data of the user; configuring the acoustic model selection module to select a plurality of acoustic models from a list of acoustic models, the plurality of acoustic models selected from the list including a first language, a first degree of proficiency, a second language, and a second degree of proficiency from the user profile of the user; employing, at the decoder module, a first acoustic model corresponding to the first language and the first degree of proficiency of the user, and a second acoustic model corresponding to the second language and the second degree of proficiency of the user based on the language skills included in the user profile of the user, the language skills indicating languages spoken by the user and, for each language spoken by the user, a degree of proficiency; and performing speech recognition at the decoder module on speech data representing speech by the user speaking in the first language using the first acoustic model, and, switching from the first acoustic model to the second acoustic model being triggered based on automatic identification of the user switching from speaking in the first language to the second language, causing the decoder module to perform speech recognition using the second acoustic model, wherein the decoder module interacts with the language model and lexicon module and the grammar module to perform the speech recognition.