Abstract Some of the most important sound changes in Old English and in Latin are introduced, and their implications for the identification and dating of loanwords examined. Approaches from word geography are considered, and particularly the light they can shed on loanwords shared by a number of different early Germanic languages. Finally, the important contribution of semantic borrowing to the Old English lexicon is examined, and some loanwords and semantic loans from similar semantic fields are compared. The chapter is followed by a brief summary of the main conclusions from chapters 6, 7, and 8.