The RadTreeList control gives you the opportunity for hierarchical representation of the underlying data like in a treeview. So first of all your data, to which the RadTreeList is bound needs to be hierarchical. Then in order to have checkbox into the treelist column you could use TreeListCheckBoxColumn column or a TreeListTemplateColumn where you could add any control into its ItemTemplate. More information and live example you could find on this link:
I hope this helps.
the Telerik team
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