Review of data in the literature on the quality of life and its assessment in chronic obstructive lung disease and in bronchial asthma. The authors mention the most frequently used types of questionnaires and results achieved when using them. General questionnaires include the Sickness Impact Profile or the short version of a very detailed questionnaire which has 36 questions with sub-questions (SF-36 = Short Form-36). Specific questionnaires are focused on certain questions concerning different diseases. These questionnaires include SGRQ (St. George's Respiratory Questionnaire) which is used mainly in chronic obstructive lung disease. For this disease also the CRQ was developed (Chronic Respiratory Questionnaire) but its section on dyspnoea is not standardized. For evaluation of the quality of life of asthmatic patients several questionnaires exist, in particular for children. Several questions call for further standardization. The value of questionnaires is, however, beyond dount. They elucidate the situation which does not ensue even from detailed functional examination of the lungs or immunological examination. It appraises bodily and mental functions of man, restriction of his activity, the sensation of comfort and general evaluation of his health. Thus "classical" evaluation methods are extended by now non-traditional ways of appraisal of diseases which have a high prevalence and thus also great impact in the population.