The complexity of what teachers do is incomprehensible to anyone who has not lived the experience. If one examines, in detail, the multi-dimensional, multi-layered, multi-faceted acts that a teacher performs each teaching day, it almost defies belief for it is beyond heroic. Done well, the impact is to influence students for all the days of their lives. Done well, it leaves students altered for the better. It takes a trained observer to perceive and comprehend the various acts, both overt and subtle, that a teacher carries out during the course of a school day. This is the onus of this book – to make explicit the professional tasks of a teacher in today’s fast changing world, where technology is rapidly replacing human interactions, where disinformation is daily fed to a gullible public, where funding and professional resources for schools are never enough, where students come to school carrying physical and emotional burdens that would daunt most adults, where the tasks of teachers are more demanding and more heartbreaking than ever before. How a teacher gives his or her all, and yet, manages to keep at the job without burning out is a significant feature of this book. Not only are these professional tasks identified and explained, but suggestions are offered for how new and practicing teachers may further hone those skills that each task demands. Knowing the tasks is not enough; learning to apply them successfully is the key to becoming that master teacher.