The reform adopted by the government introduces substantial amendments to the existing domestic merger control regime. These amendments have brought Spanish merger control laws more in line with EU rules and the laws of other EU Member States. However, there are a number of issues which will need to be clarified by future implementing legislation. These include the introduction of a coherent legal regime for concentrations carried out by means of a public takeover bid (particularly in cases of competing bids), the enactment of guidelines on certain issues such as calculation of turnover and the definition of undertakings concerned, and even the introduction of a short-form notification for transactions which do not raise significant competition issues (eg where there is no overlap between the parties to the concentration, as well as in other circumstances). The procedure for agreeing remedies during the firststage investigation (terminación convencional) also needs to be developed by implementing legislation.