We examine job durations of German workers using a linked employeremployee dataset. The descriptive evidence suggests that firm characteristics have a substantial influence on the job exit rate. However, the extent of dispersion in durations is not substantially lower at the firm level than for the sample as a whole, pointing to the presence of segmentation between long and short employment spells within establishments. Using the Cox partial likelihood estimator, we then examine the determinants of job exit. There is some evidence that neglecting firm characteristics biases the coefficients of individual-specific variables. Extension of the model to a competing risks framework shows that both individual and firm-level characteristics differ...