Fuel cells are an important piece in our quest for a sustainable energy supply. Although there are several different types of fuel cells, the by far most popular is the proton exchange membrane fuel cell (PEMFC). Among its many favorable properties are a short start up time and a high power density; both essential for automotive applications. Its drawback is the use of carbon supported Pt or Pt alloys as the active catalyst. The scarce resources of Pt led to significant efforts in reducing the amount of Pt used in PEMFCs. Thanks to the advancements of these efforts, catalyst stability gained increasing focus. Activity of the catalyst is important, but stability is essential. In the presented perspective paper, we review recent efforts to investigate fuel cell catalysts ex-situ in electrochemical half-cell measurements. Due to the amount of different studies, this review has no intention to give a complete overview and cover all studies. Instead we concentrate on efforts of our and other research groups to apply identical location electron microscopy and related methods to study the degradation of PEMFC catalysts.