Collar Stays aka Collar Bones, Collar Tabs or known as Collar Stiffeners in the UK.
Your dress shirt should be crisp, sparkling and fit.
Collar Stays will ensure your collar stays straight, perfectly bridged over your tie and anchor your collar as well.
Most shirts come with a pair or two of plastic ones. Invest in a nice pair of metal (usually brass) ones.
Also if you ever need a screwdriver, very MacGyver-007ish if you pull one from your collar 
Anne…
Just wanted to drop you a quick note to say thank you for a great resource.There is nothing else like your site on the net today. My friends are just going to love this site once I let them know about it….