The Dynamics of Verbal Communities committed to Science and Technology are associated to the production of new concepts and systems for explanation, prediction and control, which give rise to new questions, enhance theories, create new hypotheses, design new experiments, and ultimately are the origin of new technologies and techniques. Nevertheless, the development of new explanatory systems that engage Verbal Communities that are diverse, exhaustive, rigorous in both criticism and empirical and theoretical verification, involves that the proposed concepts are seen as powerful in explanation, prediction, and control.

The concept of metacontingency, initially advanced by Professor Sigrid Glenn, is part of this effort, and this special issue is a contribution that presents a number of similar works. The interlocked behavioural contingencies account for emerging products of social and cultural systems, and this is where their power lies; in other words, this concept and its developments are a bridge that explains the links between individual and social matters.

Cultural practices, as emerging products from metacontingencies, give rise to questions and hypotheses about conflicts between individual and social consequences, the way that concurrent contingencies operate upon individuals, and the specialisation of individual and group behaviours,

This issue presents diverse theoretical and experimental findings, and will become a hallmark of the contribution of a novel, powerful system for explaining social and cultural events.

We thank Professor Glenn and all the authors and reviewers who contributed their excellent papers to this issue. We also need to point out that the idea for this issue arose from the strong influence of our conversations with Professor João Claudio Todorov and of his work.

Finally, we thank Fundación Universitaria Konrad Lorenz for embracing this special issue, "Metacontingency Analysis, Cultural Practices and Social Issues" in the Latin American Journal of Psychology. We are sure that this special issue will become a landmark in the contributions made by Behaviour Analysis to the explanation of social phenomena, and it is very satisfactory that it is published by the Latin American Journal of Psychology, a journal with such history and influence.

Wilson López López
Luis Manuel Silva