This paper considers the problem of administrative capacity as one of the main requirements that the accession countries seeking EU membership had to meet, and as a prerequisite to the decentralization of their public sectors and public finances. The selected decentralization problems are analyzed using the cases of two countries: Romania and Poland. The results of a theoretical and practical evaluation of administrative capacity as a likely obstacle to fiscal decentralization are presented taking account of the different levels of decentralization in Poland and Romania. A comparative analysis of Romania and Poland shows that administrative capacity can be a constraint for fiscal decentralization. In Poland, the main problem is that the loc...