So I have a 1700s style corset, which, due to my bone disease, I can only wear for short periods of time and be safe/healthy. Most people can successfully wear them all day without issue and even find benefit (though I would not advise it every day). Anyways it goes over top, rather than underneath. Mine was made custom many years ago by a friend and we used springwire which in my opinion is the best way to make a corset, plastic boning is lower quality and doesn't last as long and breaks etc. Back in the day whale bone was used for a while, which of course added to the "fainting risk" because it didn't give properly like other materials do. Mine laces up from the bottom to the top. I don't wear it when I'm performing because singing in a corset, unless you're only singing like one song or two, is disadvised. But for things like the big pirate ball this weekend, where I'm only going for around four or five hours and I'm not performing are the perfect time for me to wear it.