This thesis explores how service companies can use artificial intelligence (AI) in marketing to strengthen corporate identity and gain competitive advantage. In services, where customers mainly evaluate experiences rather than physical products, corporate identity is built through consistency, trust, and the way a brand behaves across touchpoints. The study argues that AI is no longer just a back-office tool: through personalization, automated campaigns, chatbots, social listening, and AI-supported content creation, AI actively shapes how customers experience and interpret a brand. When these AI capabilities are strategically aligned with a company’s values and brand promise, they can improve relevance, responsiveness, and journey continuity—leading to higher loyalty, stronger brand equity, and better performance outcomes. However, the benefits are conditional: over-automation, opaque personalization, or intrusive data practices can undermine trust and create identity dissonance, especially in trust-sensitive sectors like banking and telecom. Therefore, ethics, privacy, transparency, and human oversight are framed as strategic requirements rather than obstacles, particularly within the EU regulatory environment. The thesis supports these arguments through Greek and international case studies (e.g., Cosmote, Alpha Bank, Aegean, Skroutz/eFood, Media Strom; Netflix, Amazon, Starbucks, Sephora, Hilton, Spotify), showing that AI becomes a powerful identity signal when it reliably improves customer experience and is governed responsibly. Overall, the thesis concludes that sustainable advantage comes not from using “more AI,” but from using AI in ways that consistently express what the brand stands for.