SQL Help

I have am having a problem writing a store procedure to update a specific record

Below is the record

” Goal:999999999 Recovery Needs:asdfewwfwe Referrals for Additional Services:dfasdfasdf”

As you can see there is three parts to the record

1. Goal:
2. Recovery Needs:
3. Referral for additional
Services:

I wrote the store proc and it works. The problem I have is If the Goal part is left “null” I don’t want to erase what is there already in the record. So I figure adding a if then statement to subquery the Goal part and leave it how it this should work, problem is I can’t figure how to do this.

SQL 2005