Graphene came to the forefront in the nanosciences in the early 2000s, in particular, when high-quality graphene with atomic thickness and two-dimensional extension in the micrometer range was isolated and the resulting novel electronic properties were demonstrated. Graphene has two unique features: lateral size up to tens of micrometers or larger and quantum confinement in an atomically thin sheet. It provides an excellent platform for exploring novel material properties, designing new materials, and enhancing material performance. Now, after extensive research for nearly a decade, graphene research has moved well beyond electronic applications and has begun to extend into a wide variety of disciplines. This expanded issue of MRS Bulletin is focused on graphene and consists of 20 articles and three commentaries that collectively address the major impact of graphene on materials science, highlight the newest advances, discuss challenging issues, explore applications, and reveal future directions.