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The surface immobilization of proteins is an emerging field with applications in a wide range of important areas: biomedical devices, disease diagnosis, biosensing, food processing, biofouling, and bioreactors. Proteins, in Nature, often work synergistically, as in the important enzyme mixture, cellulase. It is necessary to preserve these synergies when utilizing surface immobilized proteins. However, the competitive displacement of earlier adsorbed proteins by other proteins with stronger binding affinities (the “Vroman effect”) results in undesired layer instabilities that are difficult to control. Although this nanoscale phenomenon has been extensively studied over the last 40 years, the process through which this competitive exchange occurs is not well understood. This paper uses atomic force microscopy, QCM-D, TOF-SIMS, and in-solution TOF-MS to show that this competitive exchange process can occur through the …