An extensive database of published cordierite volatile contents from twenty-eight different high-grade terranes is used to investigate whether CO₂ streaming or fluid-absent melting processes prevail during the formation and evolution of granulites. In most case studies the cordierite volatile contents, calculated activities, and melt-H₂O contents are entirely consistent with a mode of origin dominated by fluid-absent melting processes. In accordance with published experimental and theoretical evidence these data suggest that CO₂ is not a prerequisite for granulite formation. Even in cases in which cordierite preserves high CO₂ contents this does not necessarily imply that fluid-saturated conditions prevailed. A cordierite may be CO₂-rich but can still be fluid undersaturated and preserve H₂O contents that equilibrated with melts formed from fluid-absent melting. In fluid-saturated case studies the mechanism and relative timing of saturation should be evaluated. It is evident from the data that most fluid-saturated granulites formed initially under fluid-absent conditions but subsequently became fluid saturated along a retrograde path.