Among the many applications of artificial intelligence (AI), virtual assistants are one of the tools most likely to grow in the future. The development of these systems may play an increasingly important role in many facets of our lives. Therefore, given their potential importance and present and future weight, it is worthwhile to analyze what kind of challenges they entail. In this chapter, we will provide an overview of the ethical aspects of artificial virtual assistants. First, we provide a conceptual (...) clarification of the term ‘virtual assistant’, including different types of interfaces and recommender systems. Second, we address three ethical issues related to the deployment of these systems: their effects on human agency and autonomy and the subsequent cognitive dependence they would generate; the human obsolescence that may cause a generalized extension of the dependence problem; and the invasions of privacy that virtual assistants may cause. Finally, we outline the debates about the use of virtual assistants to improve human moral decisions and some areas in which these systems can be applied. (shrink)