This chapter will examine whether we should expect an explanation for the Question. Does the fact that there is something rather than nothing call out for explanation? The answer to this question depends on what it takes for some phenomenon to call out for explanation. Here I will engage with some extant accounts of this notion of a phenomenon calling out for explanation, as well as the principle of sufficient reason, which in its strongest form claims that every fact must have an explanation. I will also develop my own account of when some fact calls out for explanation. I will propose that in asking whether some fact calls out for explanation we simply ask: What is the probability of that fact’s having an explanation? And here we employ the criteria of theory choice (i.e., the criteria governing our probability assignments) that we make in other contexts. To the extent that the probability that some fact has an explanation is greater than 0.5, we should expect the fact in question to have an explanation. In the case of the fact that there is something rather than nothing, the main factors relevant to determining the probability in question will be examined in subsequent chapters.