The main objective of the present work is to complete some work aimed at gaining an understanding of the interaction of phospholipid membranes containing the neutral helper lipid, dioleylphosphatidylethanolamine (DOPE), with chromosomal (linear) DNA in the presence of divalent ions such as calcium. The objective will be achieved using neutron specular reflectivity (NSR) studies, exploiting the technique of contrast variation to highlight the various components of the systems under study. The detailed structural information resulting from these studies will be invaluable in aid the rationale design of improved/non-toxic gene delivery vectors.