The book considers reasoning with questions involved in natural language dialogues. The first chapter shows the main points of interests in this area: the issue of the justification for raising a question in a dialogue, the informative content of the act of questioning in interaction with other agents, question relevance and questioning as a strategic process. Considerations of all these issues might be found among the topics of IEL as presented in the second chapter of this book. In what followed the logical ideas were tested and employed for analyses of natural language dialogues retrieved...