Abstract Reducing the emissions of greenhouse gases (GHG) like CO2 is one of the predominant concerns for ensuring sustainable future living conditions on Earth. However, current trends in globalization of production processes, just-in-time manufacturing, and increased numbers of parcel shipments due to a growing trend towards online shopping threaten to further increase GHG emissions. An analysis of GHG emissions is complex to perform since it has to include data from multiple sources and processes. The standard way to obtain an overview of the general emission impact is to perform a life cycle assessment (LCA), which is detailed in the first part of this paper. The same trend leads to an increasingly important contribution of logistics processes in the life cycle analysis of GHG emissions. Thus, the reduction of emissions in logistics is a major challenge for logistics research. Reductions are possible using a combination of IT-based and conventional methods on macroscopic as well as microscopic optimizations. However, the resulting economical impact must be considered when applying these optimizations. This article gives an overview of possible optimization approaches, augmented by a description of case studies, based on previous research projects.