The OPTMODEL family of mathematical programming procedures constitutes a completely new generation of optimization capabilities, distinct from and preferred over the older SAS/OR mathematical optimization procedures. The newer optimization procedures access new, far more scalable optimization solvers and use more accessible and extensible syntax than the older procedures. Therefore, SAS/OR users are encouraged to migrate to the newer optimization procedures. Accordingly, SAS/OR User's Guide: Mathematical Programming now includes information about the OPTMODEL family of procedures and their associated optimization solvers. Information about the older procedures and solvers is still available in SAS/OR User's Guide: Mathematical Programming Legacy Procedures.