The advent of the service-oriented architecture (SOA) paradigm is a major trend in the ICT industry at large. Based on open standards and protocols and enjoying broad-based industry adoption, it is set to revolutionize the computing and communications landscape in the years to come. Current literature abounds with articles on SOA - especially SOA implemented using Web services. However, SOA is much more than a buzz word. Being an enterprise-wide architectural style that promotes vendor neutrality, interoperability, and loose-coupling between service providers and consumers, it is rapidly becoming the de-facto foundation for enterprise architectures. Ever-increasing miniaturization allows driving intelligence down to the device level, thus favoring the adoption of the SOA paradigm in the embedded-device space, down to sensors and actuators. This will enable radically new device networking architectures and pave the way for application of a uniform communication paradigm down from the shop floor up to the top floor, thus breaking down current technological barriers. In turn, these evolutions hold the promise of greatly increasing the agility of future industrial enterprises. This tutorial exposes the foundations of the SOA paradigm in general and of its use in the device space in particular, explains how SOA for devices can be implemented using the Devices Profile for Web Services, and outlines the benefits it brings in the industrial sector, as illustrated by the ground breaking experience of the SIRENA (http://www.sirena-itea.org) project. It further plots some future directions and discusses the potential benefits of using advanced concepts like semantic Web services for automating service selection, invocation and composition, so as to facilitate rapid reconfiguration.