ABSTRACTCefiderocol is a siderophore cephalosporin designed mainly for treatment of infections caused by β-lactam and multidrug-resistant Gram-negative bacteria.Burkholderia pseudomalleiclinical isolates are usually highly cefiderocol susceptible, within vitroresistance found in a few isolates. Resistance in clinicalB. pseudomalleiisolates from Australia is caused by a hitherto uncharacterized mechanism. We show that, like in other Gram-negatives, the PiuA outer membrane receptor plays a major role in cefiderocol nonsusceptibility in isolates from Malaysia.