Hi Prazad ,
I think more information is required ; if you have multiple departments , say "HR" , "Sales" , "Planning" , "Marketing" ,... , and there are multiple employees in each department , I assume you have named ranges for each of the departments e.g. the named range HR can refer to the range =Sheet2!$A$2:$A$15 , Sales can refer to =Sheet2!$B$2:$B$9 ,...
Suppose the drop-down is in Sheet3 , in the cell B2 ; suppose your table starts from B10 and extends downwards ; then in B10 , you can have the following formula :
=IFERROR(INDEX(HR,ROW(A1),MATCH($B$2,Departments,0)),"")
entered as an array formula , using CTRL SHIFT ENTER.
HR is a named range , referring to : =Sheet2!$A$2:INDEX(Sheet2!$A:$A,COUNTA(Sheet2!$A:$A))
Departments is a named range , referring to : =Sheet2!$A$1:$D$1
Narayan