Sort based on field value

I have a “company pages” field group and a template that displays all of the companies in a grid. One of the fields in the group is INDUSTRY.

I now want to to be able to sort that “ALL COMPANIES page so it show only the companies in a particular industry.

I’d prefer using a dropdown on the page itself to select the industry — basically reload the page based on the selected industry. But another possibility is a dropdown in the menu.

Also, is there a way to do by adding a parameter to the ALL COMPANIES url?

The page I need help with: [log in to see the link]