In this paper, a dynamic decision model of the firm with a delayed adjustment of employment and investment is developed. Special attention is devoted to dynamic inefficiencies, i.e. underutilizations of the capital stock and labour hoarding. Market disequilibrium is introduced by allowing for a sluggish adjustment of wages and prices. The model of the firm is complemented by explicit aggregation, and the aggregate model is estimated for the FRG for the period 1960 to 1989. The empirical results reveal that dynamic adjustment constraints for employment and capital contributed to the persistence of unemployment in Germany in the 1980s.