ew versions of the pADL phagemid vectors pADL-20b, pADL-22b, and pADL-23b are now available. The sequence of the Amp(R) gene sequence has been modified, allowing the cloning site to be opened by either SfiI or BglI restriction enzyme. This modification results in lower background during cloning and brings more flexibility for designing libraries. The pADL vector series is a collection of phagemid vectors for controlled display on the minor coat protein III which combines HIS tag for purification, epitope tag for detection and amber stop codon for conditional display. Expression of the fusion protein is tightly controlled, eliminating issues with toxic clones and library misrepresentation.