In 1998, as deputy director of the Accession Negotiations Department in the Committee for European Integration, he oversaw and participated in numerous areas, including finance, of the negotiations for Polish accession to the European Union.
Pada tahun 1998, dia menjabat sebagai Wakil Direktur Departemen Perundingan Aksesi di Komite Integrasi Eropa, dia mengawasi dan berpartisipasi dalam negosiasi aksesi Polandia ke Uni Eropa di berbagai bidang, termasuk keuangan.