The 1990 Standards for Teacher Competence in Educational Assessment of Students (AFT, NCME, & NEA, 1990) made a documentable contribution to the field. However, the Standards have become a bit dated, most notably in two ways: (1) the Standards do not consider current conceptions of formative assessment knowledge and skills, and (2) the Standards do not consider teacher knowledge and skills required to successfully work in the current accountability and "standards-based reform" context. This article briefly reviews the 1990 Standards and their influence, describes some other lists of assessment knowledge and skills that might be considered in updating them, and then proposes educational assessment knowledge and skills for teachers that reflect current teacher assessment needs. This set of competencies should help focus the work of teachers, teacher supervisors, professional developers, teacher educators, and others responsible for teachers' assessment knowledge and skills.