The aim of this study was to determine the relationship between glottic space and breathy voice. Using a new computerized method of analysing the glottic area of video images with the Vocim computer system, 16 patients with a vocal cord palsy and 31 with non-organic dysphonia were examined. The quality of the breathy voice was assessed and correlated with the size of the glottic space during phonation. There was a positive (r = 0.70) correlation between glottic area and breathy voice in vocal cord palsy. There was no correlation (r = 0.002) in non-organic dysphonia. Therefore in this study population, for vocal cord palsy, glottic area is the dominant feature in determining voice quality. This relationship is not maintained in non-organic dysphonia.