Model 1 intergovernmental agreements (IGA) have been widely adopted. About 70 countries have officially signed the Model 1 IGA with the United States. Their goal is to combat tax evasion. The idea was based on the implementation agreements of the US Foreign Account Tax Compliance Act (FATCA), whose legal basis is the Convention on Mutual Tax Assistance. 97 countries have signed an implementation agreement and others intend to sign it at a later date. The first notifications took place in 2017, many of the others from 2018. In order for two countries to implement the AIA standard, they must have an intergovernmental agreement. To this end, the OECD makes available to the relevant authority or the CAA agreement (from page 21) a model convention. These types of intergovernmental agreements can be used by states in which the government itself has the power to impose the country on the new standard. Switzerland does not apply the CAA, but concludes bilateral agreements in the form of international treaties. Transparency groups have reacted in different ways, and some criticize the fact that developing countries have not been considered and involved.  The collection and provision of information can be so costly and difficult for developing countries that it is not possible to participate in the regime.
Instead of offering a period of non-reciprocity during which developing countries could simply obtain financial data, the only mention of non-reciprocal agreements is the reception of tax havens.  The same basic framework for the categorization of trusts is used in all IGA-FATCA 1A agreements, including the UK agreements with Crown Dependencies and Overseas Territories (CDOT) and the OECD Common Information Standard (SIR). The full version of the standard contains comments and guidelines for implementation by governments and financial institutions, detailed models and standards for harmonized technical and computer modalities, including a standard format and requirements for the safe transmission of data. This section presents all the bilateral exchange relations currently under way for the automatic exchange of information on IRS, in accordance with Article 6 of the Multilateral Convention and the CRS-MCAA, as well as within the framework of the EU. In addition, some legal systems have bilateral IRS information exchange agreements under bilateral tax treaties or tax information exchanges. With these three components, the AIOI standard provides a powerful tool to deter and identify offshore tax evasion by holding financial assets abroad. The common reporting standard (“CRS”) is a global version of FATCA, introduced by the OECD, which requires financial institutions to report information about taxpayers` accounts in reporting jurisdictions and certain companies controlled by these entities. To date, more than 100 legal systems have registered with or publicly announced their intention to implement IRS. As a result, the magnitude of the IRS reports will be much greater than in the case of FATCA. STEP is a member of the HMRC Advisory Group for the OECD Common Standard Reporting Standard (SIR) and has provided STEP members with guidance on their obligations under the Foreign Account Tax Compliance Act (FATCA) and SIR.