The QCD axion is the leading solution to the strong-CP problem, a
dark matter candidate, and a possible result of string theory
compactifications. However, for axions produced before inflation, high
symmetry-breaking scales (such as those favored in string-theoretic axion
models) are ruled out by cosmological constraints unless both the axion
misalignment angle and the inflationary Hubble scale are extremely
fine-tuned. I will discuss how attempting to accommodate a high-scale axion
in inflationary cosmology leads to a fine-tuning problem that is worse than
the strong-CP problem the axion was originally invented to solve, and how
this problem is exacerbated when additional axion-like fields from string
theory are taken into account. This problem remains unresolved by anthropic
selection arguments commonly applied to the high-scale axion scenario.