Multi-drug resistance in bacteria has steadily risen in the past decades to become one of the major health concerns of our modern society. Much adding to this concern is that multidrug efflux systems present a frequently used and flexible means for eukaryotic and prokaryotic cells alike to resist our arsenal of once potent agents. It is from the research of the many active participants of the highly appreciated and fruitful past GRCs that our knowledge on the molecular mechanisms of transport and multi-drug recognition, genetic regulation, and pharmacological modulation has gained considerable momentum. Increasingly, we understand that complex mechanisms regulate accumulation and extrusion of xenobiotics as well as therapeutic agents in eukaryotic and prokaryotic cells. This conference will also address the multidrug uptake systems that coexist with efflux systems in determining substrate accumulation. The 5th meeting on Multi-Drug Efflux Systems, will stand in the light of studying the old in order to better understand the new, according to an old Japanese saying "On Ko Chi Shin". The keynote lectures will be held in this spirit by recognized leaders in the field. Sessions will be organized such that each session will be introduced by an expert scientist giving an overview of the past and current knowledge, to provide the basis for understanding the new, i.e. results presented by known scientists as well as newcomers to the field. During the conference, we will address questions on the significance of efflux on the multidrug resistance phenotype in context of the role of uptake mechanisms, the role of efflux in eukaryotic systems, control of gene expression, and regulation on the protein level including post-translational modification. Aspects on structure and mechanism of multidrug resistance pumps and a dedicated session on methods how to study drug transporters including imaging techniques. Sessions on the role of drug transporters in pharmacology and pharmacogenomics and on approaches to control multidrug resistance in man and bacteria will complete the conference. Ample time will be given for exchange of knowledge during discussions as well as opportunities for junior scientist to present their latest data. The broad yet focused range of topics will give many of us the opportunity to lay foundation for future work by including learning from the past in the ongoing quest to tackle the problem of multidrug resistance in bacterial infections and cancer.