This paper describes two approaches to integrating standalone information processing techniques into a semantic application capable of acquiring and maintaining knowledge, which we conducted using our open Semantic Web framework of Magpie. We distinguish between integration through aggregation and through choreographing, and argue that the latter is not only simpler to realize but also provides greater benefits. The benefits were, in our experiment, related to developing a capability of maintaining and validating knowledge through an integration of down- and upstream knowledge processing tools. We describe the principles of integration and relate them to pragmatic challenges for the semantic web and to strategic directions of its evolution.