We describe, for the first time, a detailed electroporation procedure for Lactobacillus delbrueckii . Three L. delbrueckii strains were successfully transformed. Under optimal conditions, the transformation efficiency was 10 4 transformants per μg of DNA. Using this procedure, we identified several plasmids able to replicate in L. delbrueckii and integrated an integrative vector based on phage integrative elements into the L. delbrueckii subsp. bulgaricus chromosome. These vectors provide a good basis for developing molecular tools for L. delbrueckii and open the field of genetic studies in L. delbrueckii .