With the recent development of 3D models of the explosions of Supernovae, there has been a renewed interest in the observational indicators of asymmetry that might be used to probe the underlying physics of these events. Although multiple groups are attempting to conduct polarimetric observations, there is a significant reservoir of knowledge that has yet to be presented in one location. This book brings together the diverse range of information about the application of polarimetric observations in one location, and incorporates a full discussion of the underlying physics. Overall, this book provides a one-stop resource to the entire transient community interested in conducting polarimetric observations or incorporating them into their analyses.