Fusarium head blight (FHB), caused by several Fusarium species, is the most devastating disease in durum wheat. Modern durum varieties are highly susceptible to FHB, and thus a massive effort has been dedicated to understanding and enhancing FHB resistance in durum wheat in the past two decades. In this chapter, we reviewed the important sources of FHB resistance for durum breeding, including the major quantitative trait loci (QTL) from exotic sources and the minor QTL from native sources. We elaborated on recent advances in uncovering the genetic and molecular basis of FHB resistance, with an emphasis on functional genes for Fhb1 and Fhb7, and genes that inhibit virulence factors such as mycotoxins and cell wall degrading enzymes, reinforce cell wall structures, transduce signaling cascades to promote defense responses, and release antifungal metabolites. We reviewed the strategies for improving FHB resistance in modern durum germplasm, such as the genetic manipulation of known susceptible and resistance genes, genomic selection using genomic estimated breeding values, and mutagenesis and epigenetics to generate novel FHB-resistant alleles. We also discussed the recent advances in developing durum varieties with increased FHB resistance in the United States. The future of FHB resistance breeding in durum wheat holds a great promise because many elite durum germplasms carrying the major QTL including Fhb1 and Fhb7 from bread wheat and wild relatives now become available and are being used in breeding. In addition, expanding genomic and genetic resources provides useful tools to dissect the factors affecting FHB resistance expression and susceptibility in durum wheat.