This book deals with the development, application and validation of techniques for data analysis in view of supervisory control of cyclic systems, including and integrating aspects of monitoring, diagnosis and control. Two so far largely separated tools for data mining of process data are used as a basis for the presented developments. These are Principal Component Analysis (PCA) and Qualitative Representation of Trends (QRT). A pilot-scale sequencing batch reactor (SBR) for wastewater treatment is used as a case study for the major parts of the work presented. Another application is pursued regarding the analysis of flow measurement time series derived from an urban drinking water network.