In the name of Allah, the Most Gracious, the Most Merciful, contracts in Islam are concluded under this preamble. It expresses the limitation of human actions on Earth. All contracts are under God's observation and tolerance. Human authority, according to Islamic belief, is not absolute but must be lived in accordance with God's instructions. Islam and its followers periodically come into focus in global politics and the media, especially in recent times. However, a very superficial and largely false image is often conveyed. This also applies to the economy and banking of the respective countries. This book aims to correct prejudices through factual clarification. It primarily concerns the fundamental Islamic principles of civil and commercial law, which are relevant even in the Western cultural sphere when conducting business with Islamic partners.