A field can be turned into a button just like any other layout object can.
Select it in layout mode and choose Button Setup... from the format menu to specify the button action you want.
Go To Related Record is made to order for this purpose. GTRR can be dangerous in some situations, but it's pretty safe for this. Read the help system to learn more about the many options to choose from when using this script step.
If you are using Filemaker 10 or older, this thread may help fill in some of the blanks and documents the danger areas. (Filemaker 11 help, now documents the cases where this script step can have unexpected results.)
Go To Related Records is a very useful tool, but can be hazardous if you don't properly trap for errors. To learn more about GTRR, click the following link:
The Complete Go To Related Record
Thank you for a quick reply PhilModJunk!
I will read up on "Go To Related Record"