The paper investigates the link between firm-level productivity and internationalization (through exports,
imports and FDI) in the Lodz Voivodeship, Poland. Two hypotheses have been tested –self-selection and
learning by internationalization. It has been found that productivity may affect import and FDI decisions
of firms, while there is no evidence of such an effect regarding exports. At the same time, there is no
proof for learning, suggesting that within the timeframe of the analysis firms from the Lodz Voivodeship
do not experience productivity gains due to international trade or investment.