I made the t-shirt with no changes except for a high round back adjustment to see how it would fit. It's better than most about being smaller in the shoulders but is still way to big for my narrow shoulders. I love the fit from the bust down. It's the perfect amount of ease for me. I just need to figure out the best way to make an adjustment for the narrow shoulders. I'm not sure when the difference is so extreme if it's easier to start with several sizes smaller in the shoulders and size up the bottom or the other way around. Will just have to try both ways and see. Most things I've read say to use small size and add for the rest so will try that method first.