The aim of this research is to develop and introduce into phoniatric diagnostic procedures the complex methodology of vocal function assessment, on the basis of comparison of subjective and objective voice estimation. The set of complex voice evaluation ought to include perceptual examination of the voice quality with quantitative GRBAS scale as a subjective method, vocal folds vibrations in videostroboscopy as a quasi-objective method and acoustic voice estimation in Multi Dimensional Voice Program (MDVP) as an objective method. The basic assumption of this report is to prove correlation existence for vocal folds vibration quality in videostroboscopy, parameters describing acoustic wave generating by vibration system in larynx (MDVP) and perceptual subjective voice assessment (GRBAS scale) in organic and functional voice disorders. Research was conducted on 100 subjects (65 with organic and 35 with functional voice disorder), aged 7-74 years randomly chosen from population of patients treated at the Department of Phoniatrics and Audiology, Karol Marcinkowski University School of Medical Sciences in Poznań in 1996-2001 and 60 subjects as a control group without any voice disorders according to phoniatric examination. The research methodology include perceptual voice evaluation based on Japanese (Hirano) GRBAS scale adapted to Polish language, in scale 0 to 3 as well as the vibrations of vocal folds in videostroboscopy with attempt at quantification (scale 1 to 3) of selected measure and for acoustic analysis of Multi Dimensional Voice Program (MDVP) for 17 estimated parameters. Due to results and statistic analysis the own, new scale of dysphonia severity was introduced.