The replication, transcription, recombination, and repair of DNA are essential processes
in the propagation, utilization, and upkeep of genetic information. Numerous different
enzymes have evolved to catalyze the synthesis, digestion, unwinding, and unlinking
of nucleic acids that are central to genomic maintenance. The development of single
molecule techniques has allowed researchers to study the activity of nucleic acid enzymes
at an unprecedented level of detail. This chapter will review the various experimental
methods used and will discuss the type of information obtained by the study of nucleic
acid enzymes at the single molecule level.