The International Compliance Assurance Programme (ICAP) is a voluntary risk assessment and assurance programme to facilitate open and co-operative multilateral engagements between MNE groups willing to engage actively and transparently and tax administrations in jurisdictions where they have activities. By co-ordinating conversations between an MNE and multiple tax administrations, ICAP supports the effective use of transfer pricing documentation, including the MNE’s Country-by-Country report, providing a faster, clearer and more efficient route to improved multilateral tax certainty. ICAP should reduce the resource burden on both MNEs and tax administrations and mean fewer disputes requiring resolution through mutual agreement proceedings. This handbook contains information on the process for ICAP reflecting the experience and feedback of tax administrations and MNEs that participated in two pilots for the programme, commencing in 2018 and 2019.