I argue that the teleological-historical reflections of the Crisis are an effort to clarify what Husserl calls the "ultimate presuppositions" of phenomenology. I begin by describing the kind of presuppositions revealed in natural-attitude and phenomenological reflection. I then consider how the ultimate presuppositions become problematic for Husserl. After clarifying the distinction between these presuppositions and those already handled by the reduction, I consider the appropriateness of the new reflections Husserl undertakes in order to address them.