As one of the nation's leading ed researchers, Bryk knows whereof he speaks. The recent book he co-authored with colleagues in Chicago found that successful schools tackled reforms in five key areas: "school leadership, parent and community ties, professional capacity of the faculty, student-centered learning climate, and instructional guidance." None of these things seems particularly "bold." We've known about each for a long time.
But the book's authors draw the bold conclusion that we need to pursue all these areas at once to improve schools. Take just one of these items out of the mix, and see your results plummet. It's no accident that collaboration--among school staff; between schools and communities--is a central theme of the book.
Just to add some extra emphasis: I'm pretty cynical about arguments in the form of "the X things you need for y." Generally, these are pulled directly from the author's rear end. Organizing Schools for Improvement: Lessons from Chicago is different; it is not philosophical, it is a statistical, quantitative argument that these were the decisive factors separating successful from unsuccessful school improvement efforts in Chicago. For example, there are plenty of nice plots of say, scores of schools with all five factors against those with only four.