The TEAM evaluation methodology for information systems in biomedicine (Total Evaluation and Acceptance Methodology) is a unifying methodology for any computer-based information system based on a three dimensional framework; these dimensions being Role, Time and Structure. The theory is derived from how the information system relates to the general system where it should operate, the properties of information flow within a general system and the relation between a system and its models. As a system can in theory be modelled from many perspectives, a perspective to be modelled is built up by formulating criteria relevant to that perspective which can be evaluated by quantitative and qualitative assessment methods. Key characteristics of the methodology include the insistence on a global rather than partial approach to the evaluation of information systems, also the dynamic nature of an information system which is continually in modification as it more successfully deals with the inherent complexity of the environment in which it is operating. The role dimension identifies four main categories, designer, specialist user, end user and stakeholder from which several sub-categories may be identified. The time dimension has four main phases towards relative stability of the information system. The structural dimension distinguishes strategic, tactical or organisational and operational levels that often are confused together with risk of dilution in current approaches. It is believed that this framework and methodology can provide a basis for future standardisation of evaluation methodologies.