How does the European Union integrate new values into the text of its treaties? A growing body of literature indicates that, in the past three decades, new norms and values have entered the EU's discourse, resulting in what is usually termed ‘normative power Europe’. Yet the research and knowledge to-date about the EU's discursive assimilation of new values and norms is surprisingly poor. As any institutional change, such integration has the potential to undermine the coherence of the EU's identity and thus also its objective to ‘speak with one voice’. This article explores the EU's discursive management of the continuity-versus-change imperative by analysing the integration of new values into the text of its treaties. This issue is addressed based on a quantitative content analysis on the full texts of European founding treaties between the 1950s and 2009. Findings show that the distribution of the EU's values in the text is not uniform: while the language of market economy and democracy is pervasive, the values of peace, European identity, rights and social justice are mentioned less frequently and in restricted linguistic environments. To account for the differences in the integration of values into the EU's treaty discourse, the article develops the notion of a discursive mechanism of differentiated value integration (MDVI). This rationale echoes the logic of differentiation in policy implementation employed by the EU. It is claimed here that, applied in the European discursive arena, MDVI allows radically different readings of the same text. This helps the EU to maintain a coherent value identity while at the same time enabling change.