A taxonomy of 31 multiple-choice item-writing guidelines was validated through a logical process that included two sources of evidence: the consensus achieved from reviewing what was found in 27 textbooks on educational testing and the results of 27 research studies and reviews published since 1990. This taxonomy is mainly intended for classroom assessment. Because textbooks have potential to educate teachers and future teachers, textbook writers are encouraged to consider these findings in future editions of their textbooks. This taxonomy may also have usefulness for developing test items for large-scale assessments. Finally, research on multiple-choice item writing is discussed both from substantive and methodological viewpoints.