Background: The present analysis is a continuation of studies carried out in the same plant during the economic transformation and after the restructure. It is aimed at indicating variations in sickness absence, its extent and morbid causes in persons who leave their jobs due to various reasons (disability pension, retirement pension, plant under economic constraint, agreed change of affiliation, or a workerśs notice to terminate the employment contract). Materials and Methods: The study was carried out in a large transport industrial plant during its economic transformation (1989ś1994) in a group of 8588 workers, and after its restructure (1997ś1999) in a group of 2702 workers. The analysis was based on such absence parameters as the age standardized sickness absence rate, sickness absence cases and the average duration of sickness absence. The linear regression and Poisson regression models were used in the analysis. Results: The onset of the transformation was characterized bya growing number of workers who got retired or applied for disability pension prior to the period of redundancy procedures. After the restructure, affiliation changed to the private sector prevailed (44% of the staff), and the second place was occupied by the termination of employment contracts due to economic reasons (25%). The analysis revealed that sickness absence among workers who left the plant in 1989ś1994 was twice as high as that among workers who continued their employment, whereas among workers who left their jobs in 1997ś1999 it was 50% higher in men and 20% higher in women than that among workers who continued their employment. The highest rate of sickness absence was noted in 1989ś1994, when workers applied for or left due to disability pension. This rate accounted for about 25, which means that those workers had failed to work one fourth of the required time. Diseases of the circulatory, respiratory and musculoskeletal systems formed the major group of causes of applying for disabilitypension. A high rate of sickness absence was noted in the group of workers discharged because of economic reasons. Interestingly, after the restructure of the plant sickness absence in this group of workers did not diminish, on the contrary it increasedboth in men (21%) and women (8%) mostly due to mental disorders and diseases of the musculoskeletal system. In 1989ś1994, the sickness absence rate among men who continued their employment was 3.46 on average, and it remained low during the whole periodcovered by the study. In 1997ś1999, this rate fell to 3.09. In the former period, the sickness absence rate among women was higher accounting for 5.87 and in the latter it decreased to 3.89% (a 34% decrease). The lowest rates were observed in workers who joined the private sector in 1997ś1999 (2.29 for men and 3.48 for women). An analysis of dynamics showed that the decrease in the risk of sickness absence was significantly depended on the proportion of workers leaving the job because of the enterpriseśs economic constraints, and the increase in the average duration of sickness absence, especially in the onset of economic transformation, was also dependent on the percentage of workers discharged because of economic reasons. Conclusions: The plant restructure as a result of economic transformation in Poland contributes to the increase in sickness absence mostly through earlier retirement, disability pensions and discharge because of economic reasons. The increase in sickness absence is determined by still longer duration of sickness absence, as the number of identified cases decreases with the increasing lapse of time following the transformation.