This topic was suggested to me by Dr. Strassmeier perhaps because I was asked to speak on a very similar subject 16 years and 102 symposia ago. The task of comparing the theories of planetary and stellar dynamos is more onerous today. The subjects have advanced very considerably in that time and some of the apparent similarities between the fields are now seen to be illusory. Nevertheless, a few threads remain, some of which I will touch on in this presentation.