Hippocampal long-term potential (LTP) is the primary model for investigating mechanisms and processes involved in the establishment of certain forms of explicit memory in the mammalian brain. During the last decade much progress has been made in elucidating the cellular mechanisms underlying the induction and early expression of LTP. In contrast, little is known about the prolonged maintenance of this phenomenon. The sustained duration of LTP, however, is a prerequisite for its postulated role in information storage. In this chapter, I shall focus on results relevant to the prolonged maintenance of LTP, and show that the cellular processes involved in LTP are consistent with those believed to underlie learning and memory formation.