---
title: "async(group:qos:flags:execute:)"
framework: dispatch
role: symbol
role_heading: Instance Method
path: "dispatch/dispatchqueue/async(group:qos:flags:execute:)"
---

# async(group:qos:flags:execute:)

Schedules a block asynchronously for execution and optionally associates it with a dispatch group.

## Declaration

```swift
@preconcurrency func async(group: DispatchGroup? = nil, qos: DispatchQoS = .unspecified, flags: DispatchWorkItemFlags = [], execute work: @escaping @Sendable () -> Void)
```

## Parameters

- `group`: The dispatch group to associate with the work item. If you specify NULL, the block is not associated with a group.
- `qos`: The quality-of-service class to use when executing the block. This parameter determines the priority with which the block is scheduled and executed. For a list of possible values, see doc://com.apple.dispatch/documentation/Dispatch/DispatchQoS.
- `flags`: Additional attributes to apply when executing the block. For a list of possible values, see doc://com.apple.dispatch/documentation/Dispatch/DispatchWorkItemFlags.
- `work`: The block containing the work to perform. This block has no return value and no parameters.

## See Also

### Dispatching Work to Groups

- [async(group:execute:)](dispatch/dispatchqueue/async(group:execute:).md)