$.extend() Example var target = { a: 1, b: 2, c: 3 }; var source1 = { c: 4, d: 5, e: 6 }; var source2 = { e: 7, f: 8, g: 9 }; $(function(){ $('#targetBeforeDisplay').html($.toSource(target)); $('#source1Display').html($.toSource(source1)); $('#source2Display').html($.toSource(source2)); $.extend(target,source1,source2); $('#targetAfterDisplay').html($.toSource(target)); }); label { float: left; width: 108px; text-align: right; } p { clear: both; } label + span { margin-left: 6px; } fieldset { width: 360px } $.extend() Example $.extend() Example target (before) = source1 = source2 = target (after) =