N-terminal protein sequence information continues to play a significant role in modern structural and molecular biology.  N-terminal sequencing (also called edman sequencing) is most commonly used to identify unknown proteins, confirm protein identity and quality (often for quality control of recombinant proteins), and identify protein N-terminus and cleavage sites. Long sequences of 50 amino acids or more are possible with this technique.

N-terminal sequencing utilises the well-established Edman degradative chemistry, sequentially removing amino acid residues from the N-terminus of the protein and identifying them by reversed phase HPLC.  Pure proteins (>90%) usually generate easily interpreted data, but insufficiently purified protein mixtures may also provide useful data.