As banks around the world gear up to meet tough Basel III regulatory standards, Islamic lenders face a source of uncertainty that could prove expensive for them: how regulators will treat their deposits. Because interest payments are not allowed by sharia principles, Islamic banks obtain deposits mostly through profit-sharing investment accounts (PSIAs), which are generally considered to be more volatile than conventional deposits. Islamic banks are expected to be required to offset that volatility under Basel III by increasing the amount of high-quality liquid assets (HQLAs) which are in short supply. The PSIA issue may increase pressure on central banks and governments around the Islamic world to address some longstanding problems in Islamic finance. One is the small supply of HQLAs.