The complex nature of macromolecular interactions usually makes it very hard to identify the molecular interactions. This is especially evident in the caes of biological systems where the complex interaction of molecules in various situations may be responsibile for driving biomolecular interatins themselves but also has a broacdes effect at the cell and/or tissue level. This review will endeavor to further the understanding of biomolecular interactions utlizing the isothermal tiration calorimetry (ITC) technique for thermpodynamic characterization of two extremely important biomaterials systems viz., peptide self-assembly and nonfouling polymer modified surface. That advantages and stortcomings of this technique will be presented along with a thorough review of the recent applicatio of ITC to these two areas. Furthermore, the controversies associated with the enthalpy-entropy compensation effec as well as thermodynamic equibrium state for such interactions will be discussed.