Background: International guidelines recommend critically ill adults receive more protein than most receive. We aimed to establish the feasibility of a trial to evaluate whether feeding protein to international recommendations would improve outcomes, in which 1 group received protein doses representative of international guideline recommendations (high protein) and the other received doses similar to usual practice. Methods: We conducted a prospective, randomized, blinded, parallel-group, feasibility trial across 6 intensive care units. Critically ill, mechanically ventilated adults expected to receive enteral nutrition (EN) for ≥2 days were randomized to receive EN containing 63 or 100 g/L protein for ≤28 days. Data are mean (SD) or median (interquartile range).