On May 1, 2004, the new EC Merger Regulation went into effect, replacing the origi-nal Regulation No. 4064/89 of December 21, 1989. The fundamental philosophy of the former merger regulation has been maintained in the new ECMR, but with some substantial changes and innovations, from both a procedural and substan-tive point of view. It should be noted that the new ECMR is accompanied by a whole panoply of newly revised or issued implementing regulations, guidelines, notices, etc. to assist in the interpretation of key provisions of the ECMR or to set out procedural matters. In addition, some of these documents in the reform package deal with issues which derive logically from the exercise of merger control—for instance, the treatment of ancillary restrictions related to the transaction in question (as part of the reform package, a new European Commission notice sets out European Commission policy on that issue). In some cases, the new collection of guidelines and notices leads to new ways to deal with old problems.