Exchange traded funds have become an essential part of our financial landscape: they stand globally for $ 1,3 billion assets, 2% of listed securities and 5% of all investment funds, and constitute also for the retail investor an attractive alternative to the traditionally managed funds. Their legal regime needs further analysis especially also due to the multiple forms they can adopt, and the innovations in the regulation of investment funds. The different hypotheses are analysis, including the application of the new regime under the Alternative Investment Funds directive. Systemic issues may receive a new answer on the basis of this directive.