A preliminary discussion is presented of the advantages and disadvantages of the comprehensive assessment system used to complement the National Curriculum that is being introduced in England and Wales as part of the 1988 Education Reform Act. Some of the early findings of the Primary Assessment, Curriculum, and Experience (PACE) study are also presented. As the National Curriculum is implemented, assessment of all children against attainment targets will be conducted and Standard Assessment Tasks (SATs) will evaluate the progress of children at ages 7, 11, and 14 years, with a final assessment at age 16 years. A study involving 88 teachers in the period prior to the first administration of the SATs indicated a sense of constraint resulting from the new requirements, with many worries about the time and practicability of the innovations and their impact on the teaching-learning relationship. Little recognition of a positive role for these assessments was apparent. Interview data for 48 6-year-old children indicated anxiety on the part of students as well. It is concluded that the fundamental incompatibility of formative and evaluative assessment purposes has resulted in the loss of the powerful positive potential of assessment in promoting learning. (SLD)