Between molecules of water, there are primarily hydrogen bonds as the dominant intermolecular forces. These hydrogen bonds occur due to the polar nature of the water molecule, which has a partial positive charge on the hydrogen atoms and a partial negative charge on the oxygen atom. This leads to an electrostatic attraction between the partially positive hydrogen atom of one water molecule and the partially negative oxygen atom of another water molecule. Additionally, there are also weaker forces like London dispersion forces and dipole-dipole interactions present between water molecules.