The German Chemical Society (GDCh) is one of the worlds largest and most important chemical science societies with around 30,000 members from science, business and the liberal professions. Every two years, the GDCh organizes the GDCh Science Forum 91AV (WiFo for short) at different locations in Germany, at which chemistry is presented in all its breadth as an integrative scientific discipline. The main focus is on the topics of synthesis and catalysis, life sciences, materials, energy, resources and environment. A trade exhibition will accompany the congress.