Moving Data from one form to another.

Question

 Hey, Ok I am using C#, VS 2010, and developing windows forms.  My question is this:  I have been ask to add a new function to the existing code.  What I have is, Form1(STR) and on this form I have a box called Provider.  When I click inside this box it brings up another form(Provider Choices) which gives me ablity to select data, all I have to do is type in the first letter or all of the name and it will give me all the data that starts with that letter or the name I typed in. I have added another button to this form (Random Select) which takes me to the new form(grid view) I have developed and what it does is selects randomly three records and this works great, displays them.  Now when I select the record I want, I need to pass this back to form(Provider Choice), that I just came from and have the record to display in the box that is provided.   Then I should click OK on this form show up on the STR form (first form) and be happy that everything has been updated and go my marry way.   This another new fucnction for me and I certainly would appreciate anyones help.  You all have been great when I have asked other questions.  I have been at this C3 for 6 months, maybe someday I will get a little better at it....

Ben