Sequencing batch reactors (SBR) can provide a high level of treatment and have potentially great flexibility in their modes of operation enabling the operator - in principle - to adjust the way the SBR operates to provide the desired treatment goal. In practice, however, SBRs are most often operated using simple phases with fixed time intervals. Advanced control techniques can be used to enable an SBR to realize its full treatment potential and maximize its capacity and this paper describes several online measurements and control approaches that can be used to do so. A case study is presented that demonstrates how first a process model was used to test three control options for the Daniel Island wastewater treatment facility in South Carolina, USA, followed by field testing of two approaches and the subsequent implementation of one of these to enable the plant to maximize its treatment capacity.