The present invention relates generally to the field of molecular biology and concerns a method for enhancing various economically important yield-related traits in plants. More specifically, the present invention concerns a method for enhancing yield-related traits in plants by modulating expression in a plant of a nucleic acid encoding a Yield Enhancing Protein (YEP). The YEP is selected from a Vacuolar Processing Enzyme (VPE) or a CCA1-like polypeptide or a SAP-like polypeptide or a Seed Yield Promoting Factor 1 (SYPF1) polypeptide or a Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) activase (RCA) polypeptide. The present invention also concerns plants having modulated expression of a nucleic acid encoding such a YEP, which plants have enhanced yield-related traits relative to control plants. The invention also provides hitherto unknown YEP-encoding nucleic acids, and constructs comprising the same, useful in performing the methods of the invention.