This chapter explores the history and fruitfulness of learning sciences research on learning in the disciplines, tracing its theoretical and empirical roots, primarily in the study of formal, school-based learning environments. In addition, a growing body of learning sciences research, in both formal and informal settings, indicates the importance and promise of moving beyond strictly disciplinary boundaries. Recent and emerging work of this type illustrates how multi-, inter-, and trans-disciplinary perspectives can inform our understandings of and designs for the complex, systemic phenomena of life-long, life-wide learning.