This conclusion presents some closing thoughts on the concepts covered in the preceding chapters of this book. The book captures pioneering efforts to map the interior of early algebra, much of which is unknown territory. It provides a structural decomposition of algebra, descriptions of precursors to and pathways into algebra, and elaborations of aspects of (pre)algebraic thinking. The book provides essential existence proofs along multiple dimensions, showing that some aspects of (pre)algebraic thinking are indeed accessible to children in grades K–6. It also offers a clear and concise statement of what early algebra is not. The book discusses necessary conditions for the successful implementation of early algebra instruction. It makes clear that the success of early algebra instruction will depend in large measure on the implementation of a discourse-oriented pedagogy, in which students and teacher grapple with issues of sense making, and in which attempts to understand the mathematics are made public and reflected on.