Current model systems employed in structural studies of bacterial outer membranes rarely mimic the lipid composition accurately. This work is aimed at producing outer membrane models based upon lipopollysaccharides, the predominant lipid component, and including a model outer membrane protein from E. coli. We aim with this proposal to firstly characterise this system as 'half a membrane' at the air liquid interface where using Langmuir methods we have precise control over the surface pressure and hence average area per molecule. The successful completion of this stage will equip us to build more complex models upon solid substrates.