This presentation describes the results of the Teacher Education and Development Study in Mathematics (TEDS-M) a collaborative study of the mathematics preparation of future primary and secondary teachers. The study explored the question of whether what future teachers learn in pre-service teacher education leads to more effective knowledge of mathematics and mathematics for teaching. The methods and results of TEDSM are examined in light of their contribution to a prospective international study of novice mathematics teachers known as The First Five Years of Mathematics Teaching or FIRSTMATH.This presentation describes the results of the Teacher Education and Development Study in Mathematics (TEDS-M) a collaborative study of the mathematics preparation of future primary and secondary teachers. The study explored the question of whether what future teachers learn in pre-service teacher education leads to more effective knowledge of mathematics and mathematics for teaching. The methods and results of TEDSM are examined in light of their contribution to a prospective international study of novice mathematics teachers known as The First Five Years of Mathematics Teaching or FIRSTMATH.