Chromatin structure plays a crucial role in the regulation of eukaryotic gene transcription. Nucleosomes and higher orders of chromatin structure repress promiscuous gene expression by increasing its dependence on the function of activator proteins that regulate transcription in eukaryotic cells. Here we review several parameters governing the dynamic interactions between transcription factors and chromatin structures. These include functions of the core histones and their modification by acetylation, histone H1, HMG proteins, nucleosome positioning, DNA replication, cooperative nucleosome-binding by transcription factors, histone chaperones and nucleosome displacement, the SWI/SNF protein complex, and higher-order domains of chromatin structure. All of these impact on the interactions of transcription factors with chromatin templates. Experimental analysis of these parameters provides new insights into mechanisms of eukaryotic transcription regulation.