The psychological and psychosocial consequences of screening for alpha 1-antitrypsin deficiency (alpha 1 ATD) were investigated when the subjects were 5-7 years old. The present study was conducted when the subjects were 18-20 years old, the foci of interest being their health, psychosomatic problems, knowledge about alpha 1 ATD and the potential effect of that knowledge on their lives and future family planning. Samples of 61 PiZ and 61 demographically matched control subjects, 18-20 years old, were asked to participate. Written, structured questionnaires covered the following items: basic familial characteristics, psychosomatic symptoms, opinions on medical check-ups, information and views on future alpha 1 ATD screening, whether the knowledge about alpha 1 ATD had affected the life and family planning of alpha 1 ATD individuals. Items concerning the "alpha 1 ATD matter" were excluded in the questionnaires given to the controls. Questionnaire data were obtained from 50 alpha 1 ATD and 48 control individuals, 41 of each being matched alpha 1 ATD-control pairs. No significant differences were found in demographic or educational backgrounds, psychosomatic complaints such as headache, sleep difficulties, stomach ache, tiredness or anxiety. Lung symptoms occurred more frequently in alpha 1 ATD subjects (p = 0.05). Six per cent of the alpha 1 ATD individuals planned working careers with a high risk of air pollution. The majority (86%) of the alpha 1 ATD subjects perceived the contact with the medical services as positive; 14% as both positive and negative. The information concerning alpha 1 ATD was assessed as satisfactory by 73%, as both good and bad by 17% and as unsatisfactory by 10%. All alpha 1 ATD subjects advocated general screening for alpha 1 ATD, the neonatal period being chosen as optimal by 94%. Half of the alpha 1 ATD individuals thought that the knowledge of their high-risk condition had affected their lives, particularly their awareness of the dangers of smoking and environmental pollution. The majority, 88%, knew that they should avoid smoking to protect their lungs. In conclusion, no negative psychosocial consequences of the neonatal alpha 1 AT-screening were found in early adulthood. The alpha 1 ATD individuals were aware of the dangers of smoking and were of the opinion that alpha 1 AT-screening should be recommended.