Nutritional approaches are the most important strategy for altering the fatty acid composition of muscle lipids (Scollan et al., 2006). Grass relative to concentrate feeding increases the content of n-3 polyunsaturated fatty acids (PUFA) resulting in a low n-6:n-3 PUFA ratio. Ruminally protected plant lipids enhance PUFA content very significantly resulting in beneficial P:S and n-6:n-3 ratios (Scollan et al., 2006). This study considered the effects of finishing steers (1) outdoors on grass ± concentrate versus (2) indoors on straw/concentrate ± a protected lipid supplement with one of two levels of vitamin E on the fatty acid composition of the m. longissimus thoracis et lumborum.