Cooperativity of protein folding is the process by which the stabalization of one portion of a protein's structure contributes to the formation of other portions of the protein's tertiary form. Proteins fold to achieve a lowest energy state, tending towards a system in which entropy is increased by changing from a polypeptide chain into a globular structure or other orientation. One folding of the protein due to non-covalent intermolecular forces will set off the next process of folding in a cascade until the final lowest energy state has been reached.