The present invention relates to a targeting system comprising, preferably as distinct components, (a) a transposon which is devoid of a polynucleotide encoding a functional transposase comprising a polynucleotide of interst; and (ba) a fusion protein comprising (i) a domain specifically binding to a transposase or a fragment or derivative thereof having transposase function; or (ii) a domain specifically binding to a (poly)peptide that specifically binds to a transposase or a fragment or derivative thereof having transposase function; and (iii) a DNA targeting domain; or (iv) a domain specifically binding to a (poly)peptide comprising a DNA targeting domain; or (bb) a polynucleotide encoding the fusion protein of (ba); and (ca) a transposase or a fragment or derivative thereof having transposase function; or (cb) a polynucleotide encoding the transposase of fragment or derivative thereof having transposase function of (ca).