This introductory chapter clarifies the focus and aims of the book. It discusses how mutually constitutive, intra-active, relations between transdisciplinary voice studies and new materialisms can enrich the understanding of how voices matter: materialize into diverse events and practices and acquire different meanings. We argue that studying voice through new materialisms opens up novel ways of exploring the active and relationally forming materiality of voicings, but also the wider material, sociocultural, human, and more-than-human relationships and world-makings in which voices emerge, affording modes of being, agency, and knowing. The introduction situates the topics explored in the volume and the approaches of the individual chapters in relation to the field and existing findings of voice studies. It also outlines the ways in which new materialisms are understood and practiced in the book.