One of the contributions of critical legal scholarship is to encourage the writer to reflect over what they are doing and why. The nature and experience of international law means that a teacher and researcher can often be assailed with self-doubt. Why enthuse young people for a subject which seems to weave between excusing the (mis)use of power and building a (unrealistic) utopia? Why research about the limits the law places on state action when powerful states seem to be able to ignore these limits? This chapter consists of my personal reflections about why it is worthwhile teaching and researching international law. If there are no critical teachers and researchers, one leaves a “walk-over” to those opinion-builders from both democratic and non-democratic states who advance an authoritarian vision of international politics. Moreover, learning to think critically about international law helps us to understand better other legal subjects close to politics (constitutional law, EU law etc.) where the law is open, horizontally formed and can be subject to rapid change.