Slice preparations of neuronal tissue are among the most commonly used experimental approaches in the field of neuroscience. They are employed for a variety of techniques addressing questions across the entire neuroscience spectrum, including immunohistochemical, anatomical, and electrophysiological methods to study the properties of individual, and networks of neurons. In the past decades, slice preparations have provided information that has allowed us to develop our understanding of the central nervous system. Unlike cultures, slice preparations leave the topography of neurons and glia intact and therefore retain a considerable degree of functionality that allows molecular, cellular, and network investigations. However, a major limitation of using acute brain slices is their life span which is limited to 6–8 h due to intrinsic and extrinsic factors. Recently, new technological and methodological modifications have proved efficient in extending the life span of acute neuronal tissue. In this chapter, we will review the mechanisms leading to tissue deterioration and describe in detail the steps required to achieve a significant enhancement in neuronal viability and longevity.