Regularly, the question on the quality of philosophical practice is raised. Practicing philosophers, policy makers, scientists and last but not least clients wonder how to assess the quality of philosophical practice. Professionals want to value the format of different practices and clients want to know what to expect from visiting a philosophical practice. Understanding the quality of philosophical practice is important for determining its value and its role in society. Quality indicators can provide such information. A quality indicator is not a norm or criterion. A quality indicator is a sign or signal evoking reflection on the structure and process of the philosophical practice and the outcomes of the philosophizing that takes place there. As quality is an abstract phenomenon related to the way or how a philosophical practice is, the quality indicator should inform us on “the how”of a philosophical practice. With respect to the philosophizing in philosophical practice, reflexivity seems to be essential for recognizing it as philosophy. Just like the color of a litmus paper points at the presence or absence of an acid in a solution, the presence or absence of reflexivity informs us about the quality of the dialogue in philosophical practice. Reflexivity deepens such a dialogue every time it is applied. When applied consciously by the philosophical practitioner it can be called intentional depth. This intentional depth determines the quality of a philosophical practice.