The International Criminal Court relies on its State Parties to incorporate, or implement, its constituent instrument, the Rome Statute, into their domestic legal systems to enable its effective functioning. First, State Parties are obliged to give effect to their explicit obligation to cooperate with the Court under the Rome Statute. Second, although not required to do so, to avoid their national legal systems being found by the Court to be unable to investigate and/or prosecute the crimes under its jurisdiction in accordance with the principle of complementarity, they should also implement the definition and prohibition of these offences in their national legal frameworks. This article appraises the status of the domestic implementation of the Rome Statute, both crimes and cooperation, in Asia. The article concludes that few Asian State Parties to the Rome Statute have incorporated the treaty’s provisions into their domestic laws in a holistic manner, with the absence of cooperation legislation, enabling State Parties to assist the Court, particularly striking.