Given how central feeling, expressing, and receiving tokens of appreciation are in our everyday lives with others, one might wonder why these are important. Are these just instrumentally valuable because they make us happier, more satisfied with our lives, and more motivated to do good things in the future? Strawson suggested that “reactive attitudes” like resentment and gratitude are valuable because they are central to regarding others as responsible agents. This chapter takes this thought seriously and argues that if gratitude and appreciation are reactive attitudes, we will need to reconceive what it means to regard someone as a responsible agent. To be a responsible agent is not just to be someone who can be held accountable for failures, but also someone who has the capacity to take responsibility in a variety of ways. The chapter concludes with remarks about why expressing appreciation and feeling appreciated matter.