The CJEU's 2022 London Steam-Ship decision exposed a critical gap in the Brussels I Recast Regulation: whilst judgments confirming arbitral awards can prevent recognition of irreconcilable judgments from other Member States, the absence of a lis pendens rule regarding arbitration proceedings creates significant risks of conflicting decisions and undermines legal certainty. The European Commission's 2025 report on the application of the Brussels I Recast Regulation acknowledges such irreconcilability risks and seeks to eliminate it. Against this backdrop, the Sorbonne Research Project has proposed a concrete solution. This panel will explore the diverging approaches across EU jurisdictions to this coordination challenge, examine the practical implications of the London Steam-Ship ruling and critically assess whether the Sorbonne proposal strikes the right balance between party autonomy, judicial efficiency and the fundamental principle of mutual trust underpinning EU civil procedure.