In　XML　Schema,　the　type　definition　mechanism　is　responsible　for　defining　types　as　well　as　passing　contextual　information,　which　may　cause　some　design　problems　such　as　artificial　types.　This　paper　proposes　a　new　kind　of　XML　schema　called　Type　Dependencies　(TD)　schema　to　realize　the　separation　of　those　two　tasks.　A　TD　schema　includes　two　parts,　a　set　of　type　dependencies　which　is　responsible　for　passing　contextual　information　and　a　complete　competition　grammar　which　is　only　responsible　for　defining　types.　It　can　help　users　to　design　better　schemas　more　easily,　since　there　are　no　problems　related　to　Element　Declarations　Consistent　(EDC)　rule　and　artificial　types　in　TD　schemas.　Furthermore,　the　expressiveness　of　TD　schemas　is　more　powerful　than　XML　Schema　and　it　also　satisfies　the　semantic　concept　of　1-pass　preorder　typing,　which　make　it　more　suitable　for　streaming　data.