This paper points to the laws and tax regulations that must be applied in business transactions between residents and non-residents in the acquisition and delivery of goods within the European Union as well as at the import and export to third countries. It also shows importance of establishing foreign currency residency, types of foreign currency operations and the ability of payment in kunas as well as foreign currencies. Role of the Croatian National Bank in the regulation of foreign exchange operations is also defined as well as the role of the tax administration in assigning VAT identification numbers and surveillance operations. This paper covers the accounting aspect of the foreign currency operations of businesses that operate within the European Union. In the acquisition and delivery of goods within the European Union entrepreneur has obligations to foreign suppliers as well as claims from foreign customers. The payment and the collection of current foreign currency operations are conducted through the foreign currency account and any resulting changes are recorded in the business books.