I ordered the med large for my 11yr old  grandson,( big boy for 11)  it had to be returned , it was a bit to long and to big in the shoulders, I reordered the small. it was a great fit except for the arms, with a little hemming, it turned out to be a sporty style jacket he loves. He looks so handsome in his new jacket, he wears a white t-shirt style shirt with it. looks great!  This is a light weight material and made well. I would recommend this.