In general, cellular internalization of macromolecular drugs encapsulated in liposomes proceeds via endocytosis. This potentially leads to degradation of the liposome-encapsulated macromolecular content within the endosomal/lysosomal compartment. Therefore, bypassing the endocytic route by conferring a direct plasma membrane translocation property to the liposomes would be very beneficial. Cell penetrating peptides, e.g. TAT-peptide, are exploited in the drug delivery field for their capacity of plasma membrane translocation. Here, we describe the preparation of TAT-peptide modified liposomes and their cellular interaction using live cell flow cytometry and imaging techniques.