Your syntax is the same as
[tt][blue]="Week No " & DLookup("[WEEK]","[tbl DATES]","[YRDAYWK]=[tbl EMPLOYEE DATA].[YRDAYWK]")[/blue][/tt]
If YRDAYWK is a numeric field in your report's record source, then try:
[tt][blue]="Week No " & DLookup("[WEEK]","[tbl DATES]","[YRDAYWK]=" & [YRDAYWK])[/blue][/tt]
If it is text, try:
[tt][blue]="Week No " & DLookup("[WEEK]","[tbl DATES]","[YRDAYWK]='" & [YRDAYWK] & "'")[/blue][/tt]
Duane MS Access MVP
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