We call this a conditional value list.
Forum Tutorial: Custom Value List?
Knowledgebase article: http://help.filemaker.com/app/answers/detail/a_id/5833/kw/conditional%20value%20list
Hierarchical Conditional Value lists: Conditional Value List Question
Feel free to post follow up questions here if those links aren't enough to get your value lists working correctly.
Thank you for your fast response.
I still don't quite understand though. I have created a value list of Schools. I have also created a List Layout to show me nam,e, school & email address. How do i get the list layout to ask me for a propt before it displays the data? At the moment, when i am clicking on the list layout which i have just created it is showing me everything.
Why would it ask you for a prompt at all?
You can have your user select a School from a value list in field 1 and then they can select a contact from a value list in field 2, with the school selected in field 1 determining what contacts will appear in the value list in field 2--all without any prompts appearing.
The relationship method describe in both of the first two links of my lprevious post provide detailed information on how to set this up. I can provide you with an additional example in a follow on post if you need it, but it would help if you first described how this portion of your database is designed so that I can make sure that my example is a good match to what you actually have.