As the labelled bond market surpasses USD 5.2 trillion (MSCI,2025), a critical gap remains in understanding whether impact is a material driver of financial performance or just a symbolic designation. This research, in partnership with BlueOrchard, addresses the drivers of performance in these financial instruments. The project looks at how specific elements factor into bond pricing, exploring how impact efficacy and reporting quality influence yields (materialiasing, or not, a greenium), credit spreads and investor demand.