A new class of non-viral transduction vectors that can be used for both in vivo and in vitro applications, including a gene transfer vector that has comparable efficiency to a viral vector without the potential for a life-threatening immune response is provided. Complexes including a cellular delivery molecule or agent that can facilitate the translocation of the complex or portion thereof into cells are also provided. The cellular delivery molecules may include one or more polymers, e.g., polyamides, dendritic macromolecules and carbohydrate-containing degradable polyesters.