Colloidal suspensions consist of micron-sized solid particles suspended in a solvent.  The particles are Brownian so that the suspension as a whole behaves as a thermal system governed by the laws of statistical mechanics.  The thermodynamic nature of these systems has allowed scientists to use colloidal suspensions as models for investigating numerous processes that typically take place on the atomic and nano-scale but are often very difficult to investigate.  In this talk I will describe how we use various experimental techniques to investigate the structure and dynamics of these systems and gain an understanding of epitaxial growth, defect nucleation, and defect translation in colloidal crystals.