This paper addresses the desideratum identified by Törner (2018), that researchers' beliefs are rarely addressed in the research literature dealing with beliefs. For this purpose, firstly a suitable theoretical framework is outlined that links the concept of belief with the research perspectives of researchers. Secondly, examples are given of how beliefs were, can and should be addressed in corresponding research on beliefs. Finally, it is shown in which ways explicating beliefs of mathematics education researchers might make their research, as well as their teaching more effective.