The answer could vary depending on a couple factors. Are the sales people's
name always in the same column? Are the months always in the same rows? (i.e.
- Sales Rep A is always in Column B, January is always in row 2.)

If that happens to be the case, it's:
=sum(sheet2!B2,sheet3!B2) etc.

Assuming this is not the case, if the month is always in the same row, but
rep is in different columns:

=sum(HLOOKUP(B1,sheet2!A:B,2,FALSE)+HLOOKUP(B1,she et3!A:B,2,FALSE)) etc.

If month is different, but rep is in the same column:

=sum(VLOOKUP(A2,sheet2!A:B,2,FALSE)+HLOOKUP(A2,she et3!A:B,2,FALSE)) etc.

If neither, I'm not sure, but someone else can probably give that...

"AM" wrote:

I have multiple sheets.
Each contains sales person's name across top and their commission per month
down the column. each sheet is for a different project.
I need to creat a summary sheet with sales person's name on top and their
total commision from all other sheets per month down the column.
So, I need to lookup sales person's name from the top row, match with month
from the left column and add all corresponding commision figures from a range
of sheets.

Appreciate any help.

Happy New Year to All.