Experimental tests of quantum electrodynamics (QED) have developed dramatically for simple systems of hydrogen and helium, but there has also been significant progress for medium-Z hydrogenic and helium-like atoms over the last few years. In this area, tests are often based on X-ray spectroscopic measurements, and here we review some key developments. Of particular interest is the status of few-electron QED in the medium-Z regime, the fine-structure Lamb shift from X-ray measurements, tests of two-electron QED, and of np subshell and excited state QED. We discuss some recent secondary tests of the data to confirm the quality and different approaches to experimental development to address the dominant systematics in this area.