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# isAsynchronous

A Boolean value indicating whether the operation executes its task asynchronously.

```
var isAsynchronous: Bool { get }
```

## Discussion

The value of this property is <doc://com.apple.documentation/documentation/Swift/true> for operations that run asynchronously with respect to the current thread or <doc://com.apple.documentation/documentation/Swift/false> for operations that run synchronously on the current thread. The default value of this property is <doc://com.apple.documentation/documentation/Swift/false>.

When implementing an asynchronous operation object, you must implement this property and return <doc://com.apple.documentation/documentation/Swift/true>. For more information about how to implement an asynchronous operation, see [`Asynchronous Versus Synchronous Operations`](/documentation/Foundation/Operation#Asynchronous-Versus-Synchronous-Operations).

---

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