This is a great sports polo shirt. the fit is true to size with a slim/sport fit (not as narrow as, for example, a ralph lauren custom fit, but narrower than a normal cut polo). It is very breathable and sweat-wicking, so perfect for tennis/golf or other sports or just everyday office wear. I'm 6ft 170lbs, 39" chest, 31" waist, medium fits me perfectly. but not too tight. Very good shirt and great deal at this price, definitely recommend.