We have several foreign keys that allows for NULLs. When we open up a table in SQL Studio Management and alter one of the columns with a value that is not allowable (not part of the primary key), it accepts the value, when it should not. It appears that when there are nullable columns in a foreign key that the foreign key doesn't work; it is bypassed. I am guessing that this is part of the functionality of SQL Server. Is there a way to get around this. I am told that there is no way to make all the columns for foreign keys in this database NOT NULL. Thus, is there a work around to get the foreign key to work when one or more of the columns is NULL?