Coarse Grained Modelling of DNA and DNA Self Assembly This thesis presents a novel coarse grained model of DNA in which bases are represented as rigid nucleotides. The model is shown to quantitatively reproduce many phenomena including elastic properties of the double stranded state hairpin formation in single strands and hybridization of pairs of strands to form duplexes the first time such a wide range of properties has been captured by a coarse grained model. The scope and potential of the model is demonstrated by simulating DNA tweezers an iconic nanodevice and a two footed DNA walker the first time that coarse grained modelling has been applied to dynamic DNA nanotechnology.