# Building Asynchronous Web Services

Asynchronous web services don't require clients to block execution while waiting for results, which can make operations run more smoothly. The topics in this section explain how to design and use asynchronous web services to perform various operations.

## Topics Included in This Section

How Do I: Add Support for Conversations?

How Do I: Design a Web Service that Involves Long-Running Operations?

How Do I: Return Information to a Client Using a Callback?

How Do I: Poll Another Service for Information?

How Do I: Control the Lifetime of a Web Service?

How Do I: Associate Code with the End of a Conversation?

Related Topics

How Do I...?

Designing Asynchronous Interfaces