Abstract: A waterborne coating composition for a cured film having improved film properties and uniform film formation comprising a binder polymer containing a reactive keto group, at least one carboxylic monohydrazide or dihydrazide or polyhydrazide compound, and a reaction moderator. More specifically, the waterborne coating composition comprises (a) at least one binder polymer comprising at least one or more copolymerizable monoethylenically unsaturated monomers, wherein at least one of the monoethylenically unsaturated monomers contains at least one reactive keto group; and (b) at least one monohydrazide or dihydrazide or polyhydrazide compound; and (c) at least one reaction moderator. Reaction moderators moderate or retard the crosslinking process before film formation occurs and then act to catalyze the film formation crosslinking reaction. The final cured film product of the waterborne coatings produced by this invention have a much higher crosslink density per unit time and a uniform film formation.