An off-line knowledge acquisition process takes IT resource messages and automatically generates a set of rules used to provide situation categories for the resource messages/events. The off-line knowledge acquisition process generates an event-to-situation mapping file for efficiently mapping situation to events in runtime. Rules are fed back into a knowledge repository and process for reuse. The off-line knowledge acquisition process provides methods to reiterate the process of mining (autonomically and/or by human interaction) to improve the rules and confidence level assigning the situation categories. A runtime categorizer component uses the event-to-situation mapping file to add situation categories to the IT resource events. The runtime categorizer uses a plurality of annotator components each capable of adding a situation annotation to incoming messages based on rules generated by the off-line knowledge acquisition process. An assessment component chooses the best situation category from those annotated by the annotator components.