Purpose – This paper investigates Smart Working (SW), a set of modern and not-conventional organisational models that are characterised by high flexibility in the choice of the working spaces, time and tools, and that provides all employees of a organisation with the best working conditions to accomplish their tasks. Specifically, the paper aims to: (i) identify whether firms adopt different SW models: (ii) explore complementarities between the elements that can lead to choose a SW model, and (iii) figure out whether contingent variables matters in the implementation of a particular SW model. Design/methodology/approach – This study is based on a continuative research initiative promoted since 2012 by the School of Management of Politecnico di Milano, i.e. the Smart Working Observatory. In order to achieve the paper goal, during 2013 we have run a survey delivered to 100 HR directors of medium and large Italian organizations to collect empirical evidence on SW phenomenon, and accomplished multiple, embedded case studies to better explain the findings achieved in the quantitative analysis. Originality/value – The paper aims to look inside the black box of SW, by unpacking the elements that can generate complementarities between the adoption of digital tools, workplace and work practice innovation. Practical implications – Managers who aim to fully benefit of SW practices should not only invest in the enabling digital technologies, but also make the complementary transformations in organisational policies and workspace settings, according the contingent conditions under which they operate.