Public school teaching is a profession in transition. Already the largest occupation in the United States, it is expanding faster than the nation's student population. Teachers of color are entering the profession at twice the rate of white teachers, reversing an exodus after civil rights victories opened many other doors to African Americans. And women are again entering the profession in greater numbers after years of bypassing the field for other opportunities. But what may be most significant--to students, schools, and the nation--is that teachers today are younger and markedly less experienced than a generation ago. Experts consider teachers with five or fewer years of experience to be still learning their craft. Although the recent recession pushed back the tide somewhat, and has likely raised the level of experience, the sheer number of novices in public school teaching has serious financial, structural, and educational consequences for public education--straining budgets, disrupting school cultures and, most significantly, depressing student achievement. Yet there has been scant discussion of the phenomenon by education policymakers. This report explores the causes, conditions, and consequences of what may be a permanent shift towards a less-experienced profession. It examines escalating levels of teacher attrition in public schools, a major source of the beginning teacher challenge. And it points to promising solutions, especially teacher induction strategies that provide the sort of targeted training and intensive support that recognizes the first years of teaching as the make-or-break opportunities they are.