This new volume of Methods in Enzymology continues the legacy of this premier serial by containing quality chapters authored by leaders in the field. The first of 2 volumes covering nucleosomes, histones and chromatin, it has chapters on methods applied to the study of protein arginine methylation, high-resolution identification of intra- and interchromosomal DNA interactions by 4C technology, and peptide arrays to interrogate the binding specificity of chromatin-binding proteins.