Reconciling accounting standards and religious principles is challenging the Islamic banks and their regulators as they adapt to new international book-keeping rules due to come into force in 2018. The new rules, known as IFRS 9, will leave their mark on all major products used by Islamic banks - from simple savings accounts to Islamic bonds - and impact their bottom-lines. Banks around the globe are gearing up to implement IFRS 9 from January 2018, posing a particular challenge for many Islamic finance contracts as they change the way financial assets are classified and measured, requiring lenders to book expected losses in advance. The problem for most Islamic financial products is that their accounting treatment can often diverge from the actual economic substance of a transaction, a key concept behind IFRS 9. This has prompted the Bahrain-based Accounting and Auditing Organisation for Islamic Financial Institutions (AAOIFI) to set up a working group to look at ways to revise its rules