Corporate responsibility is increasingly involved in corporate reputation, and so, in the economic success of a company. Car fleet operating companies are exposed to criticism and, as a direct result of this many corporate protagonists responsible for the operation of car fleets are developing measures to decrease CO2 emissions and fuel consumption. A second trend is the increasing usage of image-generating marketing actions in the worldwide ‘information society’. For various reasons, these image campaigns do not always lead to the expected improvements in corporate reputation. The crucial question is, how do these marketing actions, in the name of corporate social responsibility, relate to corporate reputation? The objective of this research is to establish rules for these relationships and to derive a new stakeholder approach to optimise corporate reputation regarding car fleet management marketing. First of all this study examines theoretical evidence in preparation for further empirical studies on the behaviour of sustainable car fleet management. With this in mind, the thesis looks at empirical evidence about the factors deemed necessary for successful responsible car fleet operation and its marketing. After conducting an online survey with more than 300 respondents, a multiple-embedded-case study with three cases, six supplementary cases, and several stakeholders represents the main part of this work. As a result, this work depicts, through three models, and via a new stakeholder approach (a combination of the three), the relationships of certain main types of firm with main types of fleet as well as the main types of marketing to support corporate reputation. Unexpected findings regarding the suitable intensity of communication to internal and external stakeholders have emerged. This approach successfully supports the design of sustainable car fleet management and a suitable arrangement of the marketing approach.