Recent calls for reporting and interpreting effect sizes have been numerous, with the 5th edition of the "Publication Manual of the American Psychological Association" (2001) calling for the inclusion of effect sizes to interpret quantitative findings. Many top journals have required that effect sizes accompany claims of statistical significance. However, too often reports of data analyses in gifted education rely on statistical significance without reporting effect size indices to help interpret quantitative findings. Without a supporting effect size index, erroneous interpretation of results can occur. This Methodological Brief addresses this concern and provides examples and guidance concerning using effect sizes in gifted education quantitative research. (Contains 1 table.)