This chapter introduces the Kyoto School philosopher Ueda Shizuteru’s Zen Buddhist philosophy of dialogue as a valuable contribution to care ethics. At its center is the notion of the mutual exchange of host and guest, a dynamic interplay in which two individuals alternate between absolutely irreducible individuality through self-expression and complete receptivity to the other. Drawing on Zen mondo, Ueda presents dialogue not merely as a method of inquiry but as both the foundation of human existence and a site of ethical transformation. Building on Gadamer’s notion of play and Vilhauer’s “ethics of play” (Gadamer's Ethics of Play: Hermeneutics and the Other. Lanham: Lexington Books, 2010), the chapter proposes a “care ethics of play” rooted in this reciprocal structure, where genuine care emerges through the freedom to alternate roles. Ultimately, it argues that such mutual care is only possible through the practice of self-negation—a letting go of the ego—revealing self-care as a necessary condition for ethical engagement.