>Hi,
>
>I wanted to add a unique column constraint in the SSMS but I just don't see how. Here is what I do:
>
>1. Right mouse click on Constraints and select New Constraint.
>2. But somehow the SSMS opens the "Check Constraints" window.
>
>BTW, I know how to add this constraint in code but wanted to try it in SSMS.
>
>What am I missing?
>
>TIA

This is not very intuitive:
http://databases.about.com/od/sqlserver/a/unique.htm

If you prefer to interact with SQL Server using GUI tools, you may also create a UNIQUE constraint using SQL Server Management Studio. Here’s how:
Open SQL Server Management Studio.
Expand the Tables folder of the database where you wish to create the constraint.
Right-click the table where you wish to add the constraint and click Design.
In Table Designer, click Indexes/Keys.
Click Add.
Choose Unique Key in the Type drop-down list.