Field studies or case studies are an attempt to study practitioners in a realistic environment. The goal is to evaluate actual performance in a precise manner, with minimal interference to standard practice. Not all the variables can be carefully controlled, but unexpected events or insights may reward the careful observer/experimenter.

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Field studies are appropriate for investigating complex issues such as an entire data management system, interaction modes, or a management strategy for team organization. These issues are not amenable to straightforward controlled experimentation but some conclusions can be drawn from a field study. Critics complain about the lack of controls and the possible influence of external factors such as organizational morale, individual motivation, and personality differences. Results are not always generalizable or replicable, but important insights or suggestions for controlled experimentation can be derived from field studies. A final criticism is that field studies tend to measure current practice rather than the improvement obtainable from new strategies.