  Sustainability (defined as 'the capacity to keep up') encompasses a wide set
of aims: ranging from energy efficient software products (environmental
sustainability), reduction of software development and maintenance costs
(economic sustainability), to employee and end-user wellbeing (social
sustainability). In this report we explore the role that sustainability plays
in software product line engineering (SPL). The report is based on the
'Sustainability in Software Product Lines' panel held at SPLC 2014.
