The specific pattern of specialization of highly industrialized countries is closely linked to factor endowments, although the correlation coefficients are probably positively biased, because the products have not been weighted with their market shares. The correlation between this pattern and market growth is much weaker. Because of the balance of payments constraint, all countries show products with net exports and with net imports. The shape of the country specific frequency distribution, determined by the specialization coefficients of the products (here called general pattern of specialization), can largely be explained by the country's size, prosperity, and possible EC membership. This general pattern can be regarded as a country specific constraint to its specific pattern. The statistical results of all sections lead to conclusions concerning economic policy.