A topic of universal concern that touches everyone, philosophy of meaning in life has roots in spiritual and religious movements in almost all cultures. Many of the issues dealt with in these movements, such as human vocation, the life worth living, our relation to what is "greater" than us, and our encounters with suffering and with death, are also discussed (even if in a different manner) in the philosophy of meaning in life. However, only recently has the topic received elaborate discussion within analytic philosophy, and become a thriving field of research. This volume presents thirty-two chapters by leading authorities in their respective subfields on a wide array of subjects in meaning in life research. The chapters are organized into six sections. Section I focuses on ways of conceptualizing life's meaning. It discusses, among other issues, whether meaning in life should be understood objectively or subjectively, the relation between meaningfulness and importance, and whether meaningful lives should be understood narratively. Section II, Meaning in Life, Science, and Metaphysics, presents opposing views on whether neuroscience sheds light on life's meaning, inquires whether determinism must render life meaningless, and explores the relation between time, personal identity, and meaning in life. Section III considers life's meaning from both atheist and theist perspectives, and examines the relation between meaningfulness, mysticism and transcendence. Section IV, Ethics and Meaning in Life, examines (among other issues) whether meaningful lives must be moral, how important forgiveness is for meaning, the implications of life's meaningfulness or meaninglessness for procreation ethics, and whether animals can have meaningful lives. Section V compares philosophical and psychological research on life's meaning, explores the experience of meaningfulness, and discusses the relation between meaningfulness and desire, love, and gratitude. Finally, section VI, Living Meaningfully: Challenges and Prospects, elaborates on meaning in life and topics such as suicide, suffering, education, optimism and pessimism. Many of the chapters deal with topics that have never before been discussed in the literature. This handbook presents ground-breaking work within a rapidly developing field and offers the first published scholarly companion to the philosophical study if meaning in life.