The European Commission’s role in the European Union is that of drafting/initiating legislation to be voted on by the Council of the European Union; of ensuring that European Union legislation, once passed by the Council, is implemented; and of negotiating international agreements on behalf of the European Union.
Working documents of the Commission are called COM documents (aka Commission of the European Communities Documents or COM docs). COM docs include Green Papers (usually policy analysis of a problem area combined with suggestions for possible legislative solutions and a broad invitation to interested parties to give the commission their input) and White Papers (specific legislative proposals).
Locating European Commission Documents
EUR-Lex, a freely available website, is the most current comprehensive source of COM docs available.