This work presents a comprehensive insight about simulated moving bed (SMB) technology, from concept to unit operation and process demonstration. A particular relevance is given to SMB nonconventional modes of operation, modeling, and design of SMB-based separations as well as to the construction and operation of SMB units. A conventional separation of a racemic mixture of (S,R)-a-tetralol by means of the FlexSMB-LSRE (R) unit is addressed to better exemplify a state-of-the-art SMB lab-scale process development and demonstration.