In many companies it is common practice to define complex tasks as projects. The scope of these projects differs, however, living in times where cost pressure domi-nates most companies strategy, efficiency-enhancing measures are required. Hence, executives are keen to know whether planned projects actually deliver an-ticipated benefits and add expected value, which supposedly result in economic profitability. Conducting a preliminary study is an approach to determine whether these requirements/needs can be fulfilled or not. A preliminary study is especially suitable for a project which structure, sequences, or goals are yet to be defined. In contrast to a usually predefined framework of large investments, however, there is no universal schema which a preliminary study should follow. In fact, factors from outside affect the process and consequently influence the result. As those factors have a significant impact on the outcome of preliminary studies, this thesis is to research, identify, and analyse the most prevalent factors. This is done by a litera-ture research and a case study. Apart from focusing on economic factors, especially corporate factors (e.g. employees and their motivation), the factors corporate culture and internal processes are considered as well. Results show the most important influence factors, like process integration, a sufficient requirements engineering and a valuable business case as well. To examine the findings of the theoretical chap-ters, a case study about a preliminary study of an Austrian bank on the introduction of a document management system is presented in the last section.