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Several results are presented concerning the existence or nonexistence, for a subset S of ω₁, of a real r which works as a robust code for S with respect to a given sequence $⟨S_{\alpha }:\alpha <\omega ₁⟩$ of pairwise disjoint stationary subsets of ω₁, where “robustness” of r as a code may either mean that $S\in L[r,⟨S{*}_{\alpha }:\alpha <\omega ₁⟩]$ whenever each $S{*}_{\alpha }$ is equal to $S_{\alpha }$ modulo nonstationary changes, or may have the weaker meaning that $S\in L[r,⟨S_{\alpha }\cap C:\alpha <\omega ₁⟩]$ for every club C ⊆ ω₁. Variants of the above theme are also considered which result when the requirement that S gets exactly...

For every uncountable regular cardinal κ, every κ-Borel partition of the space of all members of ${\left[\kappa \right]}^{\kappa }$ whose enumerating function does not have fixed points has a homogeneous club.