Mapping the genomic location to which transposons jumped is of greatest interest to transposon biologists. Transposon display (TD) is the technique of choice that is easy and fast in determining the neo-insertion positions of a target transposon. Essentially, tagging of transposon is performed by digesting genomic DNA, ligating adaptors to digested DNA ends and PCR amplifying genomic regions flanking the transposon of interest. In this chapter, the experimental procedure of TD is described using Onsen retrotransposon of Arabidopsis as an example.