Although all assessments have an amount of value, not each writing assessment that can be made is valued, and not each value created in assessing writing can be counted as valuable because of the subjective nature of writing assessment, especially essay assessment. This book aims to help preservice teachers, teachers, teacher educators, and leaders in language education to cope with essay assessment by going through the ways of measuring and assessing essay assessment with validity and the interrater and intrarater reliability of ratings which gives interesting indicators of same and/or different rater and/or scorer behavior.