The use of bidentate ligands in organometallic chemistry is best illustrated by the successful application in homogeneous catalysis1 and bio-medical2 systems. For catalytic systems the use of bidentate phosphines have revolutionised the way in which homogeneous catalysis is viewed, with the use of functionalised organic ligands to induce favourable catalytic product formation such as the production of L-Dopa3. To this end, the investigation of tropolone type ligands and complexes will be discussed further in this chapter. The possible application of tropolone systems will be investigated in the context of possible catalytic and bio-medical applications. In 1945 Dewar4 predicted that 2-hydroxy-2,4,6-cycloheptatrien-one (Tropolone, Eq. 1.1.I), would show certain aromatic properties; he specifically referred to the natural products known at that time, stipitatic acid and colchicine5 as representative of this class of compounds. Thus Dewar was the first person to point to a new field in organic chemistry, which to date has not been fully explored due to the diversity of uses of tropolone and its derivatives. / Prof. A. Roodt