Preface to the August 2018 Issue including selected works from CLEI 2017 plus one regular paper

In this special issue a selection of the best papers presented during the 42th Latin American Conference in Informatics (CLEI 2017) is presented in extended versions. After a very tough selection process for the Conference, a set of 10 paper obtained the best review marks. The authors were invited to submit extended versions that were again blind-reviewed, and finally eight were accepted for publication. A ninth regular paper completes the issue