The new SmartPEI® ready-to-use transfection reagent from Geneye is designed to enable laboratories to reach high transfection efficiency for a limited and controlled cost. Based on the proven technology of linear polyethylenimine derivative, SmartPEI reagent can provide stable performance with high batch-to-batch reproducibility. High transfection efficiencies can be reached for over 400 cell lines compared to homebrew lipid- or calcium-phosphate-based methods. With SmartPEI, transfection complexes can remain stable for up to four hours. Moreover, the compound is compatible with adherent and suspension cells and has been tested on more than 400 cell lines.