In any argument, the arguer intends the reasons to adequately support the conclusion, to imply it. For example, if you want people to conclude that your product is the best buy for them, you ought to give them some good reasons. What makes the reasons good enough is that they imply that your product is the best buy for them. This chapter explores how the notion of implication lies at the heart of logical reasoning. There are two kinds of implication that can be involved—deductive or inductive. This chapter focuses on deductive arguments, and the main goal of a deductive argument is to satisfy the standard of being deductively valid. We will define “deductive validity” very soon.