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The dimorphic yeast Candida albicans is one of the most common human fungal pathogens, responsible for both superficial and systemic infections. Study of this yeast has been hampered by the difficulty of direct genetic analysis as it lacks a sexual cycle and is naturally diploid. This project aimed to circumvent this problem by using the genetically well characterised budding yeast Saccharomyces cerevisiae as a surrogate system to identify and characterise C. albicans genes whose products are essential during the late G1 phase of the cell cycle. I have constructed two genomic libraries of C. albicans in yeast/E. coli shuttle vectors using both a low-copy-number plasmid (pRS316) and a high-copy-number plasmid (YEp24). These genomic libraries were designated CLS1 and CLS2 respectively. The libraries were used to screen for C. albicans homologues of S. cerevisiae cdc mutants by functional complementaion. I isolated three plasmid clones which rescued temperature sensitivity in a strain carrying cdc4-3 of S. cerevisiae by transforming with plasmid DNA of either CLS1 or CLS2. The characterisation of these clones showed that they also complement the cdc4-1 allele and have a 3.95kb region in common. Nucleotide sequence analysis of the insert from one of the clones revealed an open reading frame with its amino acid sequence homology to that of S. cerevisiae Cdc4 protein. This open reading frame has seven copies of the characteristic WD40 repeat in its C-terminus as found in Cdc4. In addition, the N-terminal portion of the open reading frame also displays similarity with that of Cdc4. The gene containing this open reading frame was designated CaCDC4 for C. albicans homologue of CDC4. Unlike CaCDC4, I have been unable to identify a C. albicans equivalent of CDC7 from CLS1 or CLS2 by functional complementation. Hence an alternative PCR- based approach was adopted. I have used two degenerate oligonucleotide primers derived from amino acid sequence within subdomains Via and VIII of the catalytic domain of Cdc7 to amplify DNA fragments from C. albicans genomic DNA using polymerase chain reaction. One of the fragments of about 400bp was shown to contain part of an open reading frame encoding an amino acid sequence exhibiting homology to the Cdc7 protein. This fragment was used as a probe to screen CLS1 and CLS2 by colony hybridisation. From CLS1, four plasmid clones were identified. Sequence analysis showed that one of these plasmids, pJS73 contains a gene displaying close similarity both in organisation and sequence to Cdc7. The gene was designated CaCDC7 for C. albicans homologue of CDC7. However, pJS73 failed to rescue temperature sensitivity in a cdc7-1 strain of S. cerevisiae. The significance of these results in relation to late G1 phase in C. albicans and S. cerevisiae is discussed.