Nucleosomes, the basic organizational units of chromatin, package and regulate 
eukaryotic genomes. ATP-dependent nucleosome-remodeling factors endow chromatin 
with structural flexibility by promoting assembly or disruption of nucleosomes 
and the exchange of histone variants. Furthermore, most remodeling factors 
induce nucleosome movements through sliding of histone octamers on DNA. We 
summarize recent progress toward unraveling the basic nucleosome sliding 
mechanism and the interplay of the remodelers' DNA translocases with accessory 
domains. Such domains optimize and regulate the basic sliding reaction and 
exploit sliding to achieve diverse structural effects, such as nucleosome 
positioning or eviction, or the regular spacing of nucleosomes in chromatin.