Any manager will tell you that assertiveness is a key requirement for the job. Being able to say no to your boss when they give you too much to do or to ask a wayward colleague to do your bidding requires a level of assertiveness that many people don't have.
This book by the "personal transformation expert" Dena Michelli promises successful assertiveness in a week. It's a clever idea, but rather ambitious. The book sets tasks to complete throughout the week and offers points to consider: Sunday, for example, is about exploring different communication styles; Tuesday is about dealing with the negative and becoming comfortable with saying no; and Friday is about the messages you convey through your body language.
Ultimately, successful assertiveness boils down to three main points. First, understand yourself (your values and beliefs); second, know yourself (your wants and predispositions); and third, value yourself (your confidence and rights). "From this position", writes Michelli, "you will be well placed to make choices - how you wish to be perceived and how to plan your career."