Slovenian Janez Potocnik is to succeed Belgian research commissioner Philippe Busquin and to oversee the proposed E40 million (£ million) European Commission research programme from 2007-10.
Jan Figel of Slovakia will replace Luxembourg's Viviane Reding as Education Commissioner in the new commission unveiled by incoming Brussels president Jose Durio Barroso.
The Eastern Europeans have acted as shadow commissioners since their countries joined the European Union last May. They are expected to take up their duties on November 1.
Mr Barroso is keen to dispel claims that they will carry less clout in his expanded commission of 25, despite the low profile of their countries.
Mr Potocnik faces a tough job steering negotiations over the seventh framework programme of research to implementation. With commission proposals calling for a vastly expanded budget, he will need to be persuasive at the Council of Ministers. He was Slovenia's minister for Europe and steered its EU accession.
Mr Figel, a scientist specialising in power electronics, will oversee Erasmus Mundus, the EU's initiative to become a global higher education contender, and the critical middle phase of the Bologna convergence process. He entered politics as a Christian Democrat in 1992, when Slovakia gained independence. He has been his country's foreign minister and handled its EU accession.
The commissioners could work closer together than their predecessors. Mr Barroso has pledged to stage "informal brainstorming sessions" and to "improve cooperation between departments and commissioners' private offices".
"Thematic groups" will be established to "draw together commissioners whose portfolios relate to a particular policy challenge".
Opinion, page 15