In this article we give a detailed presentation of state event logic which is a modal logic for reasoning about concurrent events and causality between events [8] State event logic differs from previous approaches in the following directions: First, events enjoy the same attention as states. In the same way as states can be viewed as models of the formulae describing the facts that hold in them we think of events as models of the formulae describing the subevents. Second, instead (...) of postulating just one set of states as primitive objects we use two sets, a set of states and a set of events In terms of modal logic, the universe then becomes a set of pairsin which the first component is a state and the second is an event following the state. The connection between two subsequent pairs is expressed by an accessibility relation.Propositional and first-order state event logic are formulated and illustrated with examplese.From these examples we can immediately infer that state event logic can also be applied for the representation of real world scenarios. Finally we added a thorough discussion on related approaches. (shrink)