So, if you put "a" in A1 of sheet4, you want B1 to show 4 (the sum of
all the a's from the other 3 sheets?) If so, put this in B1 of Sheet4:

=IF(A1="","",IF(ISNA(VLOOKUP(A1,Sheet1!A:B,2,0)),0 ,VLOOKUP(A1,Sheet1!
A:B,2,0)) + IF(ISNA(VLOOKUP(A1,Sheet2!A:B,2,0)),0,VLOOKUP(A1,S heet2!
A:B,2,0)) + IF(ISNA(VLOOKUP(A1,Sheet3!A:B,2,0)),0,VLOOKUP(A1,S heet3!
A:B,2,0)))

Copy this down as far as you think you need it.

Hope this helps.

Pete

On May 28, 6:39*pm, pierre wrote:
hello help me plz :

given :

in sheet 1 :

* * * A * *B
3 * *a * *1
4 * *b * *2
5 * *c * *3

in sheet 2 :

* * * A * *B
1 * *c * * 4
2 * *d * * 5
3 * *a * * 3

in sheet 3 :

* * * A * *B
2 * *e * *6
3 * *f * * 7
4 * *g * *8

NOW i would like to make in sheet 4 the following :
column a:a *: the search string
and i would like to receive in column b:b *their *coresponding results...

thanks