The workshop S4SI aims at addressing the multiple open questions around the realization of end-to-end sliced softwarized infrastructures and the fundamental challenges that will facilitate the envisioned intelligent orchestration and programmability of SDI, enabling faster deployment and efficient operation of integrated services across different resource domains. Such advances in future ecosystems, like 5G, are expected to enable dynamic establishment of generalized virtual function chains, according to service requirements. Visit the web site for more details.