Recent achievements in the chemical processing of ferroelectric niobates epitaxial films are reported. The molecular level designing of the precursor solution was stressed as well as the control of key processing factors. Examples are presented for LiNbO3/Ti, K(Ta,Nb)O3 and (Sr,Ba)Nb2O6 films from metal alkoxide precursors. Crystalline epitaxial films with stoichiometry could be synthesized through control of the intermediate state of starting molecules in solution. Water vapor stream was found to play an important role in crystallizing gel films to desired phases at relatively lower temperatures.