The success of structural biology methods over the past few decades has focused attention on the beautiful structures of the folded states of proteins that have been determined for many sequences. In contrast, the unfolded “state”, really an ensemble of disordered conformations, was generally regarded to be highly generic, completely random, and rapidly rearranging. This study, together with {1-5}, demonstrated recent advances in nuclear magnetic resonance (NMR) and optical methods that have started to change this view and detail how different sequences and different solvent conditions can alter the ensemble. This Recommendation is of an article referenced in an F1000 Faculty Review also written by Lisa J Lapidus.