it might also continue to wait for input. Such interactions will substantially increase the complexity of the reasoning an agent needs to perform. In this article, we have assumed that the agent is finding a transfer-of-control strategy for a single, isolated decision. In general, there will be many decisions to be made at once and the agent will not be able to ignore the interactions between those decisions. For example, transferring control of many decisions to a user, reduces the probability of getting a prompt response to any of them.

Reasoning about these interactions will add further complexity to the required reasoning of the agent.

Another focus of future work will be generalizing the AA decision making to allow other types of constraints - not just coordination constraints - to be taken into account. This would in turn require generalization of the concept of a D action to include other types of stop-gap actions and may lead to different types of strategies an agent could pursue.

Additionally, transfer-of-control actions could be generalized to allow parts of a decision to be transferred, e.g., to allow input to be received from a user without transferring total control to him/her, or allow actions that could be performed collaboratively. Similarly, if actions were reversible, the agent could make the decision but allow the user to reverse it. We hope that such generalizations would improve the applicability of our adjustable autonomy research in more complex domains.

## Acknowledgments

This research was supported by DARPA award no. F30602-98-2-0108. The effort is being managed by Air Force Resear Labs/Rome site. This article unifies, generalizes, and significantly extends approaches described in our previous conference papers (Scerri et al., 2001; Scerri, Pynadath, & Tambe, 2002; Pynadath & Tambe, 2001). We thank our colleagues, especially, Craig Knoblock, Yolanda Gil, Hans Chalupsky and Tom Russ for collaborating on the Electric Elves project. We would also like to thank the JAIR reviewers for their useful comments.