A wide variety of diseases are results of deficient or abnormal protein-lipid interactions. The elucidation of the interactions between specific proteins and lipids and the ability to examine and manipulate biomembranes that mimic real-life systems hold the key to a better understanding of these diseases. Using model membrane systems, along with various microscopy, x-ray, and neutron scattering techniques, we carry out fundamental studies on the interactions between lipids and proteins to gain insights into the biophysical aspects of various biomedical and biological problems. Our research currently covers 5 different areas: (1) lipid-protein interactions in lung surfactant, (2) the role of membrane lipids in the aggregation of Alzheimer’s amyloid beta peptides, (3) the mechanism of membrane disruption by antimicrobial peptides, (4) membrane sealing by poloxamers, and (5) lipid rafts or the role of cholesterol in lipid ordering.