Good for people at around JLPT level 3 or so, most of the language concepts and structures covered in this book will be stuff that you’re already familiar with so it’s easier to pick up whatever sprinkling of new stuff there is. New phrases are explained in the form of notes and also in a cultural context. There’s a section dealing with business proceedings in Japan in every chapter, so if you’re heading there for business this’ll be helpful. Covers adequately both informal and polite/honorific forms as well.