DOBROVIČOVÁ, Iveta: A research of unethical practices applied to consumers in the Slovak market [Diploma thesis] – Technical University in Zvolen, Department of Marketing, Trade and World Forestry. Thesis supervisor: Ing. Miriam Olšiaková, PhD. Zvolen: TU, 2021. 80 p. The main goal of the thesis is to examine the extent to which Slovak customers perceive various forms of unethical and misleading practices on the part of traders, which are often part of the various tools of the marketing mix. The diploma thesis is divided into two basic parts, namely the theoretical and practical. In the theoretical part of the work we deal with morality, ethics, business ethics, the institutionalization of ethics in business through corporate codes of ethics and areas that are related to the issues addressed. In the practical part of the work we focus on a questionnaire survey, which was focused on finding out to what extent Slovak customers register selected deceptive and misleading practices committed by traders. An important part of the practical part was the testing of established hypotheses. At the end of the work, we present the results and conclusions that we reached by evaluating the questionnaire survey.