phiC31:int-mediated recombination has been used to integrate the TS58A2xSce vector into the M{3xP3-RFP.attP'}ZH-58A landing site. The M{W+G+R+.TS58A2xSce} construct contains: Dmau\mariner 5'ITR - w+* marker - RS(I-SceI) site - 442bp of genomic sequence homologous to sequence flanking one side of the landing site - Avic\GFP3xP3.cUa marker - 1000bp of genomic sequence homologous to sequence flanking the other side of the landing site - RS(I-SceI) site - Disc\RFP3xP3.PB marker - Dmau\mariner 3'ITR. The RS(I-SceI) sites can each be used to induce a double stranded break which is repaired by the single-strand annealing pathway. Due to the configuration of the construct, in each case this leads to deletion of a transposable element end plus a marker gene, resulting in stabilisation of the transgene.