Coordination and Adaptation are two key issues when developing complex distributed systems. Coordination focuses on the interaction among software entities. Adaptation focuses on solving the problems that arise when the interacting entities do not match properly. This is the report of the fourth edition of the WCAT workshop, that took place in Berlin jointly with ECOOP 2007. Previous editions the workshop dealt with general issues which mainly served for a better characterization of Software Adaptation as an emerging discipline within the field of Software Engineering. For this edition, we wanted to put the focus on practical approaches for software adaptation, in order to show how this discipline helps in the construction of current software systems