This book is scientifically grounded and empirically rich. In the book, Dr Peter T Keo argues that critical humanity is compassion and empathy in action to improve the lives of the worlds suffering. However, leaders must close the gap between what they say and the actions they take. Critical humanity has four key components. First, it favours action over passivity. Second, it favours collectivism over individualism alone. Third, critical humanity requires living in the space / tension between compassion and empathy. Fourth, it requires leaders to close the gap between what they say / believe and their actions, i.e., their espoused values and their action items, respectively. Dr Keo refers to this gap throughout the book as the values gap, because it is a constant tension between the what I say / believe and the what I am actually doing to truly impact the communities served. Public servants and public service leaders -- for whom this book was primarily written -- can have a deeper and more meaningful impact by embracing all four components in their service to humanity. While the contents of this book are empirical in nature, at baseline, it is an expression of Dr Keos personal truth, an epistemology that shares, in equal measures, the joy and pain of a life that is both hopeful and sceptical in humanity. It is an expression that recognises the tremendous shortcomings and opportunities, again in equal measures, of leaders to properly and authentically serve historically marginalised populations. Dr Keo had arrived at this realization after decades of embodying the life of a child of Cambodian genocide, war, systemic racism, and poverty. He has experienced life in disenfranchisement in two separate but related occasions, which have shaped his epistemology. The stories that have formed the impetus for and, indeed, triggered the curiosity undergirding this book, is this: the entanglement of misery and joy is the very essence of life. It is the curiosity of this entanglement -- and the need to drastically untangle them to improve the lives of the worlds suffering -- that compelled Dr Keo to write this book, and to develop this new idea: critical humanity.