Fullan (2015) describes leadership from the middle as:
...a deliberate strategy that increases the capacity and internal coherence of the middle as it becomes a more effective partner upward to the state and downward to its schools and communities, in pursuit of greater system performance. The goal of LftM is to develop greater overall system coherence by strengthening the focus of the middle in relation to system goals and local needs. Thus, it is not a standalone, but rather a connected strategy. This approach is powerful because it mobilizes the middle (districts and/or networks of schools), thus developing widespread capacity, while at the same time the middle works with its schools more effectively and becomes a better and more influential partner upward to the center. (p.24)
Fullan, M. (2015). Leadership from the middle: A system strategy. In Education Canada (55)(4). pp. 22-26. Canadian Education Association.