The University of Pennsylvania is one of the partner institutions of the Complex Materials Consortium, a Collaborative Access Team (CMC CAT) developing and maintaining two beamlines at the Advanced Photon Source (APS), the third generation synchrotron source at Argonne National Laboratory. CMC CAT offers its users a liquid surface spectrometer (LSS). This instrument guides a steering crystal that bends the x-ray beam down to the surface of a liquid sample while keeping the sample itself level. Another arm of the LSS positions the detector to count photons scattered in the reflection or in-plane geometries. With a Langmuir trough mounted on the LSS sample stage, we can investigate the structure of molecular monolayers at the water/vapor interface.