Being and Time (German: Sein und Zeit) is a 1927 book by the German philosopher Martin Heidegger. Although written quickly, and though Heidegger did not complete the project outlined in the introduction, it remains his most important work. Being and Time has profoundly influenced 20th-century philosophy, particularly existentialism, hermeneutics and deconstruction. The book is dedicated to Edmund Husserl "in friendship and admiration".