As the field of service design matures, questions concerning the nature of its practices, their impact, methodological gaps, potentials, limitations and claims, are timely, but unlik ely to result in simple answers. This Special Issue of International Journal of Design seeks articles from academics and practitioners that explore the tensions and paradoxes within service design and service marketing at a time when factors of difference and diversity make negotiating complexity a central challenge for its practice. How might service design adapt its approaches to attend to complexity and diversity? In an age of globalisation, what can be learnt from the diversity of local practices and know-how? How does service design navigate strategy development in complex business environments? What role can service design have in the transformation of systems, super systems and policy? How can service designers work effectively across the multiple dimensions and levels of a system or organisation or in response to the challenge of diverse, differently empowered stakeholders? Is the model of the designed service a lever to shift old modalities into the new or a brake on such possibilities? How might designers engage respectfully with Indigenous knowledge? The special issue seeks to explore these and other ambiguities and frictions.