The thirties (extending through the war into the forties) was a period of intense and rapid philosophical development for Levinas. He absorbed the revolutionary implications of phenomenology in the presence of its masters Husserl and Heidegger, and then eﬀectively introduced this philosophy into France. In his own ﬁrst publications, he explored the intoxicating freedom of these theories, and then had to revise his enthusiasm upon discovering Heidegger’s endorsement of Nazism. As a result, he then began more patiently and painfully to construct the intricate ideas and approaches that were to underpin his mature ethics. So this chapter traces Levinas’s initial indebtedness and subsequent questioning of phenomenology, it reads in detail some of the key explorations of experience, temporality and the emerging Other which Levinas elaborated during this period, and it points up the important connections to the later, major, works.