The same burning question that haunts sewers when attaching a sleeve to an armhole also bedogs makers of intimates. To set elastic flat or in the round? One way is easier than the other, but the other way is considered the correct method. Most of the big pattern companies inexplicably have sewers set sleeves in the round, so that’s the method they learn first. But once he or she tries the flat method, they usually never go back. Of course, the project at hand has some say in the matter (i.e. setting a sleeve in a t-shirt versus a tailored jacket). Same goes for attaching elastic. Newbies are first taught to set elastic in the round, but never go back after trying the flat method. For me, the correct method is the one that yields the higher quality finished product, which in the case of undies is setting the elastic flat on the leg opening and setting the elastic in the round at the waist. Here’s why. The leg opening is curved, so it is a lot easier to set it flat. However, the waist opening is straight (not curved), so it’s not a hassle setting the the round. The only difference to consider when choosing between the two is how the elastic will be finished. When setting in the round, you will most likely overlap the elastic 1/2″, which is flatter than when elastic is set in the round. In that case, the elastic will have to be finished separately and tacked either forwards or backwards.