This master’s thesis called Business Ethics and Sustainable Development is divided into six major units, starting with the introductory part which contains the discussion of the main issues and a brief summary of everything that will be discussed in the following chapters. The next section provides a general overview of ethics and business ethics. In the following chapter, the notion of sustainability and sustainable development is clarified, continuing with a separate part that points out the links between business ethics and sustainable development. Related to that, a primary survey is conducted in the form of a poll consisting of 18 questions conducted on a sample of 116 respondents. The main goals are to analyze the existing care for sustainable development and ethics in business among the respondents, and on the basis of the collected data to provide an insight into the state of knowledge of individuals about the concepts of sustainable development and business ethics. The subsequent hypotheses are that the employees are familiar with concepts of business ethics and sustainable development during their work experience, and that Croatian companies do not pay sufficient attention to sustainability, sustainable development and business ethics. In the end, conclusions and overview of the whole thesis are given.