The present invention provides thermosetting aqueous binder compositions of one or more cyclic enamine, including bis-enamines and di- or higher functional enamines, optionally containing a water soluble or dispersible or dispersible primary amine compound. The binders are at least substantially formaldehyde free, need no polycarboxylic or polycarboxylate component, and yet provide excellent hot wet tensile strength when cured for as little time as a minute or less in use.