This book proposes a logical framework to specify and analyze the knowledge of the observers of a concurrent-distributed computational system. Such a system could be a computer network, a financial market, a biological/ecological system, or a social network. The system is observed by agents who are trying to obtain information about it and about the other observers – the competitors. The logical framework allows one to analyze the flux of information in this kind of scenarios and to design strategies to obtain or exchange information. It is a framework conceived for addressing questions regarding communication and security issues. Formally, this work combines two successful paradigms from Computer Science: Process Algebras and Dynamic-Epistemic Logics. Starting from the observation that Process Algebras generalize the modal Kripke structures, this work proposes the Dynamic-Epistemic Spatial Logics which extend the Dynamic-Epistemic Logics developed for epistemic Kripke structures to the more general case of Process Algebras. Thus, this new class of logics combines features of process logics such as Hennessy- Milner and Spatial Logics with Epistemic Logic.