Eine ethisch sensibilisierte Sichtweise auf die Finanzmaerkte und den von dort ausgehenden externen Effekten gibt Anlass zur tiefgruendigen Hinterfragung finanzwirtschaftlicher Wert- und Normengefuege. Die kritische Finanzethik praesentiert sich als Unterstuetzerin in diesem Prozess, indem sie auf Basis eines kritischen Rationalismus zur Begruendung von Leitlinien verantwortlichen Handelns in der Finanzwirtschaft beitraegt. Gezeigt wird, welche theoretischen Ueberlegungen ihr zugrunde liegen und was sie als Orientierungskonzept zu leisten vermag. (It is financial crises that most clearly point to ethical problems inherent to mathematically structured financial markets. If not now, when else to question the moral grounds of finance? The approach of Critical Financial Ethics claims to illuminate the genesis and characteristics of these ethical problems. Arguments offered are based on revealing the profound connections between financial theory, acts and impacts. It can be demonstrated that the financial sciences which nowadays dominate practical market action is not free of bias, ignores spill-over effects and follows its own myopic ideological argumentation in many ways. To momentous effects, financial theory not only tries to model human behaviour, it also conditions it. In combination with a mindset disconnected from responsibility for financial actions, there is little chance to avoid ethical problems except by exploring capitalism’s more subtle workings. In conclusion Critical Financial Ethics professes that our personal financial actions must never exceed our capacity to oversee our money’s whereabouts or its effects. This would be a fundamental step to-wards reducing the harm to people and environments from finance, whether it be in crisis or in ascension.)financial markets, socially responsible investments, sustainability, business ethics