The Communication scenario editor (called scenario editor from now on) is a tool in which a communication expert iteratively develops a communication scenario as a directed acyclic graph of steps, and specifies the respective scores and feedback per step. The editor balances usability for a non-programming (communications) expert and expressiveness of the constructs in which a scenario can be expressed. Besides the standard sequence, choice, and conditional options, the editor offers interleaving and premature endings. Interleaving is particularly useful when students have to perform multiple (sub)tasks, but the order in which these tasks are performed is not important. Premature endings enable a player to skip the following steps in a sequence. Interleaving and premature endings add expressiveness to the editor, and give the author the possibility to obtain a high-level view of a scenario. Other important features of the editor are the possibility to specify learning goals for a scenario, and to specify the emotional effect and the score on (some of) the learning goals of the choice of a player for a particular statement. None of the existing editors on for example the Unity store, such as Dialoguer, or Simple Dialogue Engine Asset, combines the features of the scenario editor. The editor is implemented in JavaScript and runs in a web-browser. The output of the editor, a dialogue, is stored as an XML file. To use a scenario in a game, use the step-based competency assessment asset.