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There is an urgent need to improve the efficacy and range of antifungal drugs due to a global increase in invasive fungal infections, which are difficult to treat and are associated with high rates of mortality. Developing new drugs is expensive and time consuming and synergistic therapies that enhance the efficacy of current drugs are an alternative approach. Iron chelators have been used as antifungal synergents in salvage therapy, however, how these cause synergy are unknown. This thesis aims to use a transcriptomic approach to understand the mechanistic detail of antifungal-chelator synergy in the pathogen Cryptococcus to find potential antifungal targets. It focuses on amphotericin B (AMB) and lactoferrin (LF) synergy and voriconazole (VRC) and EDTA antagonism upon screening the interactions of various antifungal - chelator combinations in Cryptococcus. LF was found to enhance the antifungal effect of AMB in two ways: via the dysregulation of stress responses and metal homeostasis that disrupted the cell’s ability to mount an appropriate stress response, and by overwhelming the cell’s stress response via the cumulative strain from ER stress, disruption of transmembrane transport processes and increased metal dysregulation. Metal homeostasis was vital to both processes and the direct disruption of metal homeostasis, via deletion of iron (Aft1, Cir1 and HapX) and zinc (Zap1 and Zap104) regulating transcription factors, resulted in increased AMB susceptibility. Analysis of drug-binding domains in Zap1 and Zap104 found these to contain druggable sites and be potential antifungal drug targets. EDTA in the presence of VRC was found to disrupt mitochondrial functions along with an up-regulation of drug efflux genes, suggesting a potential mechanism of antagonism by mediating the efflux of intracellular VRC. Overall, metal regulation is important for resisting antifungal stress and is a potential antifungal strategy, where Zap1 is a potential antifungal drug target.