The application-layer based control loops of dynamic adaptive streaming over HTTP (DASH) make video bitrate selection a complex problem. In this talk, I will review and present new insights into the challenges of DASH rate adaptation. I will identify several critical issues that contribute to the degradation of DASH performance with respect to the rate control loops of DASH and TCP. In addition, I will introduce a novel DASH quality adaptation algorithm SQUAD, which is specifically designed to ensure high quality of experience (QoE). This is followed by an overview on the implementation of the SQUAD algorithm and its comparison to a number of state-of-the-art quality adaptation algorithms. Through extensive experiments on both testbed and cross-Atlantic Internet scenarios, we show that by sacrificing little to none in average quality bitrate, SQUAD provides significantly better QoE in terms of number and magnitude of quality switches.