These pages provide some information about the analysis of rhythmic structures of physiological signals (especially electrocardiogram / instantaneous heart rate and a respiratory signal). This work is carried out at the Chair of Medical Theory and Complementary Medicine of the University of Witten/Herdecke and the Gemeinschaftskrankenhaus (Community Hospital) in Herdecke, Germany. An important aspect of our current work and research is the development and application of methods to explore the rhythms/oscillations of heartbeat and respiration of the human organism by means of time series analysis (e.g. heart rate variability). We use established methods to analyse 24h-electrocardiograms. In addition to the analysis of a single time series we also investigate the interaction of two time series, e.g. cardiorespiratory synchronization or cardiorespiratory coordination. This work aims to incorporate the most recent advances in the field of time series analysis.These methods are used to provide scientific evidence for the efficacy of remedies and therapies of complementary , especially of those which affect heartbeat and/or respiration. In a study on Cardiodoron®, a remedy of the anthroposophic medicine, and on anthroposophic therapeutic speech the methods from time seris analysis could be successfully applied.