Automatically Update Master Sheet from multiple other sheets

I need suggestions/help to build a macro.

The case: Four departments need to be able to input data in a worksheet. Each department has their own worksheet (SheetJ,SheetK,SheetM,SheetN). The data then needs to aggregate into a master worksheet (SheetMaster). One additional sheet, Sheet1, needs to be ignored for the macro.

I want any update to Sheet J,K,M, or N to automatically update on Master Sheet. There is a unique identifier (client ID) used within each department. If the Client ID is matched across two or more departments, I want to avoid a duplicate being created on the Master Sheet.

Any help would be greatly appreciated.