If an undertaking holding a dominant market position engages in price discrimination without any objective justification, this will raise concerns under competition law, particularly Article 22(1) of the AML. Therefore, this chapter explores how abuse of dominance is assessed under the AML and its policy instruments. Relevant rules and case law provide insights into defining the relevant market, determining market dominance, and assessing price discrimination. In particular, Sect. 2.2 illustrates how to define a dominant market position through a typical guiding case, in which the internet security company, Qihoo accused the multinational technology company, Tencent of abusing its dominant market position by means of restraining the transaction and tying. The administrative penalties imposed by the SAMR on Alibaba (for abuse of dominance by restricting undertakings operating on the platform, Alibaba to only conduct transactions with Alibaba) and CNKI (for abuse of dominance by restricting academic journal publishing units and universities to only conduct transactions with CNKI and selling Chinese academic literature online database services at unfairly high prices to obtain substantial monopoly profits) are also briefly discussed in relation to the definition of relevant markets and the determination of dominance in digital markets. Section 2.3 examines how price discrimination can amount to an abuse of dominance and explores objective justifications for this alleged abusive behaviour. Given that algorithmic pricing has become a reality facilitated by the rapid growth of Big Data and algorithms, the remainder of this book will analyse whether the “traditional” approach can effectively tackle concerns arising from (AI-enabled) price discrimination in digital markets.