Oliver used the term "articulation" synonymously with “horizontal articulation" or "correlation." He equated the concept of "continuity" with "vertical articulation."51 Regarding correlation as a halfway move toward integration, I would articulation are all interrelated. I would separate continuity from vertical articulation and define continuity as a reintroduction of content at progressively more complex lev- els and articulation as the meshing of the curriculum of the various levels of the educa- tional ladder to provide for smooth transition on the part of the learners. This meshing may or may not involve reintroduction of units of content, progressively more difficult. When speaking of articulation, I am addressing the problem of vertical articulation. agree with calling correlation horizontal articulation. Sequence, continuity, and