In higher eukaryotes, all cells contain the same DNA sequence but different cell types carry out vastly different functions. This ability is regulated by a dramatic reorganization of the genome during cell differentiation, whereby packaging of DNA into a compact chromatin structure, termed heterochromatin, results in the transcriptional silencing of specific genes. Conversely, transcribed regions of the genome are maintained in an open chromatin structure termed euchromatin. Compacting of DNA into heterochromatin is a complex process, which involves the function of many factors that regulate and fine-tune the accessibility of the transcriptional machinery to the DNA. In my talk, I will discuss how recently developed electron microscopy (EM) methods can be applied to visualize chromatin in isolation and inside the nucleus. Firstly, single particle cryo-EM analysis for high-resolution structure determination of reconstituted chromatin complexes. Secondly, electron tomography combined with correlative light and electron microscopy (CLEM) of cells. Together, these imaging techniques provide complimentary structural information about how DNA-binding proteins regulate gene expression.