The presence of complexing agents in waste solutions increases the difficulty of removing heavy metals, such as copper. Treatment methods for electroless copper rinse waters depend greatly on the particular copper complexing agent used in the electroless copper process. Treatment methods to be discussed are grouped into three categories, chemical, physical, and electrochemical. The chemical methods include substitution, reduction of the metal ion, oxidation of the complexor, and ion exchange. The physical methods are evaporators and reverse osmosis. The electrochemical methods are electrolytic plate out, electrowinning and electrochemical displacement.