Responsive Web Design is basically a series of techniques where we adapt content based on the capabilities of the browser. This adaption is mostly done client side, but not all browsers, and especially not mobile browsers, are capable of doing this. Another approach is to do most of the adaption server side. In this talk we will see how we can combine the best of both worlds by combining client side techniques with server side components. We will also have a look at how we use these techniques to solve some of the difficult tasks in responsive design: responsive images, ads, video and caching.