  Schur rings are a type of subring of the group ring that is spanned by a
partition of the group that meets certain conditions. Past literature has
exclusively focused on the finite group case. This paper extends many classic
results about Schur rings to the infinite groups, including Leung-Man's
classification of Schur rings over finite cyclic groups. Additionally, this
classification will be extended to all torsion-free locally cyclic groups.
