This tutorial book presents an augmented selection of the material presented at the Second Pernambuco Summer School on Software Engineering, PSSE 2007, held in Receife, Brazil in December 2007.The 8 contributions are the thoroughly revised versions of the papers presented by the invited lecturers. The revision was inspired by the synergy generated by the opportunity for the lecturers to present and discuss their work among themselves, and with the school 's attendees. The courses cover a wide spectrum of topics in software engineering with a special focus on testing - a key activity for assuring software quality. Apart from foundational issues, languages and techniques, the courses also cover the semantic underpinnings of refinement, as well as industrial applications and refinement tools.