STEMCCA reprogramming kits are lentiviral based reprogramming technologies that utilize a single polycistronic cassette encoding the four reprogramming factors, Oct4, Sox2, Klf4 and c-Myc, termed "Stem Cell Cassette (STEMCCA technology)" to efficiently reprogram mouse embryonic fibroblasts (MEFs) and human foreskin fibroblasts (HFFs) into iPS cells. The use of a single lentiviral vector instead of four separate vectors for the derivation of iPS cells significantly reduces the risks of insertional mutagenesis and viral reactivation and is a step towards safer utilization of iPS technology for clinical therapies.