Welcome back. Last week, we learned a lot about urban sanitation both at the city-wide and at the community level. This week, we'll provide a systematic overview of the sanitation value chain and the relevant technologies that are applicable to urban settings. At the start of our second week, we would like to highlight a useful document that we will be using during the next weeks: The Compendium of Sanitation Systems and Technologies. This book was first published in 2008 and has just now been republished in an updated second version. It has gained popularity among engineers and planners because it structures the whole range of urban, peri-urban and rural sanitation technologies in low and middle income countries in one single document. The Compendium is available both as hard copy, and in an interactive, online version called the eCompendium. The Compendium has since been translated into several languages shown here and can also be downloaded from the website given here. The Compendium is divided into two parts, and is color-coded for easy reference. The first part provides an overview of nine basic sanitation systems, ranging from the most simple, the single pit system, to the complex, sewerage system with urine diversion. The second part, shown here on the right, consists of 57 technology information sheets which describe tried and tested sanitation technologies. Each of these fact sheets explains how a technology functions and for which system it can be used. Now there is also an online version of The Compendium of Sanitation Systems. It's called the eCompendium. Compared to the print version, it offers the user easy navigation within the Compendium. For example, on the system templates, you can choose the different technologies that you'd like to look at. Given here by a gas reactor, you simply click on that and it takes you directly to the technology. There is also a filter function, which facilitates the combination of suitable technologies and links to the SSWM tool box. The eCompendium also allows you to study the different technologies in detail and is linked to the SSWM tool box with a lot of additional information, case studies, further reading, training material and videos on the different technologies presented. And finally, the eCompendium also offers a complete glossary of environmental sanitation terminology that provide a short and precise definition of all terms covered in the Compendium.