Every year, significant numbers of immigrant children from Mexico enter classrooms in the United States. These immigrants comprise a heterogeneous group of students with diverse needs, abilities, and experiences. Transnational and Borderland Studies in Mathematics Education is the first collection to offer research studies across these communities. Providing invaluable research on both sending and receiving communities in Mexico and the US, this collection considers the multiple aspects of children’s experiences with mathematics, including curriculum, classroom participation structures, mathematical reasoning and discourse – both in and out of school – and parents’ perceptions and beliefs about mathematics instruction.  An important treatment of an insufficiently documented subject, this collection brings together researchers on both sides of the border to foster and support an interest in documenting evidence that will set the stage for future studies in mathematics education.