This demo illustrates how to merge grouped columns in the ASPxGridView. In this mode, a user can group grid data by multiple columns at once and combine them into a single grouping level. Drag a column header to the group panel and merge it into an existing group level. Rearrange those merged column headers to reorganize and reorder the grid data. To remove a column from the merged groups, drag it back to the column area of the grid.
Set the MergeGroupsMode property to Always to enable merged grouping.