The phenomenon of genomic imprinting, whatever its biological functions and evolutionary origins may be, ultimately manifests itself in the monoallelic expression of certain genes. The assumption has been, therefore, that the transcriptional regulatory systems of imprinted genes would directly or indirectly represent the principal focus of the imprinting process. As this chapter will discuss, however, our perceptions of gene regulation mechanisms are currently undergoing a radical re-evaluation and some of the emerging concepts may prove to be of importance to our understanding of how genomic imprinting functions.