Candida guilliermondii (teleomorph Meyerozyma guilliermondii) is an ascomycetous species belonging to the Saccharomycotina CTG clade which has been studied over the last 40 years due to its biotechnological interest, biological control potential and clinical importance. Such a wide range of applications in various areas of fundamental and applied scientific research has progressively made C. guilliermondii an attractive model for exploring the potential of yeast metabolic engineering as well as for elucidating new molecular events supporting pathogenicity and antifungal resistance. All these research fields now take advantage of the establishment of a useful molecular toolbox specifically dedicated to C. guilliermondii genetics including the construction of recipient strains, the development of selectable markers and reporter genes and optimization of transformation protocols. This area of study is further supported by the availability of the complete genome sequence of the reference strain ATCC 6260 and the creation of numerous databases dedicated to gene ontology annotation (metabolic pathways, virulence, and morphogenesis). These genetic tools and genomic resources represent essential prerequisites for further successful development of C. guilliermondii research in medical mycology and in biological control by facilitating the identification of the multiple factors that contribute to its pathogenic potential. These genetic and genomic advances should also expedite future practical uses of C. guilliermondii strains of biotechnological interest by opening a window into a better understanding of the biosynthetic pathways of valuable metabolites.