This paper summarizes the experiences acquired during the European research project, "On the Move," and draws on some conclusions on how mobility will impact information service providers. The paper begins with a definition of mobile information systems and explains the On the Move project; the goal of On the Move is to develop a "mobile middleware," a software that intercedes between the computer and the communications device and manages connectivity in the manner best suited to this. Following an examination of the aspects of mobility is a discussion of the information aspects, especially how the information demanded changes when the user can access it free from constraints in time and space. Discussion then moves to how this information can be obtained by the provider, which existing systems can be used and which new systems and information must be created. The paper concludes with a discussion on presentation aspects, as the same information will need to be presented in different ways, depending on the user terminal and the transmission network capabilities. (Contains 21 references.) (Author/AEF)