A simple, non-invasive acoustical method is developed to detect respiratory phases in relationship to swallows without the direct measurement of airflow. In 21 healthy subjects (4–51 years) breath sounds are recorded at the trachea and at five different recording locations at the chest wall, with simultaneous recording of airflow by a pneumotachograph. The chest signal with the grestest inspiratoryexpiratory power difference (‘best location’) is either in the mid-clavicular line in the second interspace on the left or third interspace on the right. Using the ‘best developed and achieves 100% accuracy in the estimation of respiratory phases without using the measured airflow signal. Thus, acoustically monitoring breaths and swallows holds promise as a non-invasive and reliable assessment tool in the study of swallowing dysfunction.