Coalesce and ISNULL not grabbing columns with NULL

I am trying to combine data from two tables. 1 table has a column where a value could be NULL. When I run my select, I never see the row with the NULL value. Here is my commandSELECTCOALESCE (ISNULL(k.Application, ''), ISNULL(n.Application, '')) AS ApplicationFROM Table1 kINNER JOIN Table2 nON k.Application = n.ApplicationGROUP BY COALESCE (ISNULL(k.Application, ''), ISNULL(n.Application, ''))