Cellular ageing appears to consist mainly in a loss of adaptability and a progressive decrease in the capacity of the cell to maintain homeostasis. Such age related phenomenon can be the result of stochastic or of programmed events, and may occur through changes in the base pairs or coding of the DNA, through increasing levels of error in transcription and finally through alterations at the translation step of proteins synthesis. The purpose of this chapter is to present histone acetylation as a key event in the control of chromatin structure and transcription.