In an era of growing environmental impact awareness, businesses stand at a crossroads. CMOs and CIOs must champion the transition to sustainable marketing technology (martech) together. This report explores the compelling reasons for this necessary transformation, including legal mandates, corporate social responsibility (CSR) and disclosure demands, evolving customer expectations, and the pursuit of sustainability for tangible business benefits. It outlines a best practice approach for B2B leaders to drive marketing technology decisions with sustainability as a primary motivator.