Techniques for performing diagnostics for a monitored system. In one set of embodiments, an aggregate model can be built from a set of models corresponding to entities (e.g., applications and systems) in the monitored system, and data from the monitored system can be applied to the aggregate model. Diagnostic result information can then be generated based on the application of the data to the aggregate model. In certain embodiments, generating the diagnostic result information can include determining a state of an application or system in the monitored system and determining an impact of the state to a user.