The present invention relates to a targeting system comprising, preferably as distinct components (a) a transposon which is devoid of polynucleotide encoding a functional transposase comprising (aa) a polynucleotide of interest and; (ab) a DNA sequence specifically recognized by a DNA binding domain; and (ba) a fusion protein comprising (i) said DNA binding domain; or (ii) a (poly)peptide binding domain binding to a (poly)peptide comprising said DNA binding domain; and (iii) a DNA targeting domain; or (iv) a (poly)peptide binding domain that binds to a cellular or engineered (poly)peptide that comprises 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 or fragment or derivative thereof having transposase function of (ca).