Updated project metadata. Decoding protein C-termini is a challenging task in protein chemistry using conventional chemical/enzymatic approaches. With the rapid development in modern mass spectrometer, many advanced mass spectrometry (MS) based protein C-termini analysis approaches have been established. Although great progresses have been continually achieved, it is still nec-essary to develop more efficient approaches in order to discover a proteome-scale protein C-termini (C-terminome), and consequently to help understand their biological functions. In this report, we describe a simple method, termed BaSCX, for basic strong cation exchange chromatography, to study C-terminome.