Emerging distributed computing scenarios (mobile, pervasive, and social) are characterised by intrinsic openness, decentralization, and dynamics. As a consequence, the effective deployment and execution of distributed services and applications calls for open service frameworks promoting situated and self-adaptive behaviours, and supporting diversity in services and long-term evolvability. This suggests adopting nature-inspired and/or socially-inspired approaches, in which services are modelled and deployed as autonomous individuals in an ecosystem of other services, data sources, and pervasive devices. Accordingly, the self-organizing interactions patterns among components and the resulting emerging dynamics of the system, as those of natural systems or of social systems, can inherently exhibit effective properties of self-adaptivity and evolvability. Although many initiatives (like those named upon digital/business service ecosystems) recognise that the complexity of modern service systems is comparable to that of natural ecosystems, the idea that nature – other than a mean to metaphorically characterize their complexity – can become the source of inspiration for their actual modelling and implementation is only starting being metabolised. The idea behind the ASENSIS workshop emerged in the context of the European Research Project “SAPERE: Self-aware Pervasive Service Ecosystems” (http://www.sapere-project.eu), with the goal of bringing together researchers and practitioners (from both inside and outside the project itself) interested in nature-inspired solutions for modern service systems. And, altogether, to spend a day involved in scientific and technological discussions about many challenges related to the modelling, design and implementation of adaptive service ecosystems in natural and social terms, and identifying promising approaches and solutions.