A distributed shared log is a data structure that allows multiple process to observe a consistent and totally ordered view of events that occur in a distributed system. This project aims at designing and implementing a highly efficient distributed shared log named Global LOG, or simply GLOG, that will provide the following features: support for geo-distributed operation, support for subscribers with different consistency requirements, and support for clients that are only concerned with a subset of the information in the log. Thus GLOG will combine features of classical logs with features of publish-subscribe systems, in a unique combination of flexibility and global consistency. The project will also implement GLOG-KV, a geo-replicated, sharded, multi-consistent transactional key-value store built on top of GLOG. GLOG-KV will support partial replication and transactions with different semantics.