The elucidation of the structure of amyloid fibrils and related aggregates is an important step towards understanding the pathogenesis of diseases such as Alzheimer's and Parkinson's, which feature protein misfolding and/or aggregation. However, the large size and poor solubility of amyloid-like fibrils make them resistant to high-resolution structure determination. Here, we describe the use of hydrogen-deuterium exchange coupled with NMR as an indirect strategy to determine the folding regions of amyloid-forming proteins at residue level resolution.