>>

>>To use the RI Builder
>>
>>In the Database Designer, create a relationship between two tables, or double-click the relationship line to edit the relationship.
>>In the Edit Relationship dialog box, choose the Referential Integrity button.
>>In the Referential Integrity Builder, select the rules you want to enforce for updating, deleting, or inserting records.
>>Choose OK, and then choose Yes to save your changes, generate RI code, and exit the builder.
>>

>
>
>That worked, I have forgotten the basic over time.
>
>Thanks
>Nick Patel

In addition you may want to take a look to Walter Meester RITaxBuilder in Download section here.
It has several advantages comparing with the native RI Builder. I used this file with success.