This research is done within the framework of an ongoing debate in the field of instructional design about the locus of instructional control that is best suited for multimedia learning environments. A dominant, constructivist approach voices that the learner should have all the control over the sequencing of the instructional material. Learners should be stimulated to explore an ill-structured learning environment in their own pace, in order to construct a personal mental model of the domain. In doing so, the effectiveness and efficiency of the learning processes greatly improves, and also the self-efficacy of the student is positively influenced. Self-efficacy has been found to be an excellent predictor of students attitudes and accomplishments. An additional advantage is that students discover how to learn, as they make decisions and experience the results of those decisions. They will acquire strategies for learning in different situations. However, not all students may benefit to the same extent from the suggested amount of instructional freedom. The results of recent studies of Shyu and Brown indicate, that although all students appear to benefit from learner control opportunities, those students with a higher content domain experience and/or ability benefit the most. Gray (1986) posits that learner control is more efficient only under the condition that the learner has a well-established conceptual understanding of the content domain. In instances where the learner does not possess the necessary knowledge, motivation or interest to make informed or correct choices, he could easily leave holes in their understanding. In a learning environment that is set up according to a schema driven approach, information tends to be organized as a compact representation of the knowledge. Consequently, by nature of design, this environment diminishes the control that the learner has over the path through which the information is explored and therefore shifts the locus of control away from the learner towards the learning environment. This research is done in the broader context of the ParlEuNet-project (acronym for Parliament European Network). The aim of the project is to ask the help of students to solve an authentic, complex and current real-world problem, revolving around the European Parliament. The problem consists of challenging prespecified subproblems that can be tackled from a variety of perspectives, and have no straight solutions. Some of the subproblems require the use of various technological facilities consisting of both communication tools (e.g., videocon-ference, internet, e-mail, fax and telephone) and information tools (e.g., WWW, databases, CD-roms, and documents available in the library). A dedicated multimedia database has been set up to permit the downloading of educationally relevant and useful information via the internet, that otherwise would not be electronically available to the public. The students can access the database in either an open or in a scaffolded mode. In the open mode, no (implicit) guidance is provided, all information is accessible. The student has the freedom to choose his or her learning path, based on own intentions, strategies, preferences, and pace. In the scaffolded mode, guidance is embedded in the access of the information in the database. The scaffolded access mode entails only the first presentation of information that is considered to be most important. When a student wants more or other information, he/she can go to the rest of the database or even to the internet. The research questions of the Maastricht University are twofold. First, we want to have some answers to the question of how the learning outcomes are influ-enced by the two different access modes to the database. The second research question identifies the way in which the construction of the database is influenced by the amount support that is offered.