Ok, so I have a FormView with a Customer dropdown, and a Location dropdown. The Location dropdown is dependant on the Customer dropdown.

"Easy," I think. But no. The Location drop down works when it and the Customer dropdown is placed outside the Formview. But when they are both inside the formview they don't as they aren't in the right scope(or whatever). I've tried CustomerDropDown, but to no avail.

Anyone have any ideas on how to manage this?

By doing it programatically rather than using the designer?

I tried using FindControl as in: 

DropDownList Customer = (DropDownList) FormView1.FindControl("KundeDropList");

Maybe you need to post some of your code here. The FindControl function should return the required DropDownList.

1      protected static Control FindControlRecursive(string Id, Control Root)
2      {
3        if (Root.ID == Id)
4          return Root;
5    
6        foreach (Control Ctl in Root.Controls)
7        {
8          Control FoundCtl = FindControlRecursive(Id, Ctl);
9          if (FoundCtl != null)
10           return FoundCtl;
11       }
12       return null;
13     }

(lifted from http://www.west-wind.com/WebLog/posts/5127.aspx) and using  

1    DropDownList Customer = FindControlRecursive("KundeDropList", FormView1) as DropDownList;

And setting selectedvalue manually.

Thanks for your help cwlaualex! (That's quite a nick, does it mean anything? Different language?)