Under the Sharia (Islamic law), riba or interest is forbidden. As divine and immutable law, there can be no differentiation between sacred and profane acts in Islam. All human activities, including financial transactions, must therefore be structured according to the Sharia. Bankers must therefore understand the moral basis of divine law. Islamic banking principles involve much more than riba however. For although riba is usually translated into English as "usury", it also has a much broader meaning under the Sharia as "increase" or "gain". Conventional bankers trying to structure new financial products for the Islamic market have to take into account a second common term gharar which can be translated as uncertainty, speculation or risk.
It was reported that at the beginning of 2000, Islamic banking was growing at a a rate of 15 percent per annum.