Fossil fuels are limited resources and are anticipated to be exhausted within the next few decades. Solar energy is the only renewable resource capable of adequately meeting today's total global energy demand. Dye-sensitised solar cells (DSCs) represent a novel class of photovoltaic devices that mimic nature's photosynthesis process. This book focuses on the possibilities of optimising the dye-sensitised solar cells' efficiency, and also presents the historical background of DSCs, their efficiency timeline, key components, and the principle of operation. Some powerful nanotechnology tools and methods used to investigate and enhance this type of solar cell are also presented in detail. The methods and findings detailed here combine both experimental and computational studies. They pave the way towards enhancing the efficiency of dye-sensitised solar cells.