run macro only if condition is met

[Nikonov]

I need to run a macro (copy one cell into another) only if a certain
condition is met. For example, if x=a, then run this macro. If not, do
something else.

 

[Gary''s Student]

Sub Macro1()
If Cells(1, 1) = 1 Then
Exit Sub
Else
MsgBox ("HI")
End If
End Sub

 

[Don Guillett]

Didn't you answer it

if x="a" then
run thismacro
else
do something else
end if