Multiple-documents literacy refers to the ability to locate, evaluate, and use diverse sources of information for the purpose of constructing and communicating an integrated, meaningful representation of a subject, issue, or situation. In Norway and many other countries, researchers, educators, and policy-makers are concerned that this crucial competency is not adequately developed through schooling. In this basic research project, upper-secondary and undergraduate students' multiple-documents literacy wi thin the domain of science will be focused. Specifically, based on existing theory and research pertaining to multiple-documents literacy, three questions will be addressed. First, which learning processes and competencies are involved in the comprehensio n and integration of multiple documents and how are those processes and competencies interrelated? In order to investigate this issue, we will conduct a study where first-year university students read authentic documents presenting different views on a na tural science topic. The documents will be presented digitally in a controlled Google-like environment and represent different kinds of source materials. Second, how can the learning outcomes of multiple-documents literacy be reliably and validly assessed ? To address this question, existing tools for the assessment of single-document comprehension will be further adapted to the reading-task context of multiple documents. Moreover, validation research will be carried out that compare scores on adapted vers ions of existing assessment tools with performance evaluations derived from additional sources. Third, how can multiple-documents literacy be effectively promoted? To investigate this issue, we will conduct two experiments in upper-secondary school. Exper imental groups will be given instruction when searching and reading documents on the Web to learn about a conflicting scientific topic. Multi- and single component approaches will be compared with control conditions