# send(_:to:completion:) Sends a custom type to other participants in the group session. ``` final func send(_ value: Message, to participants: Participants = .all, completion: @escaping ((any Error)?) -> Void) where Message : Decodable, Message : Encodable ``` ## Parameters `participants` The recipients of the message. The default value of this parameter is the set of all active participants in the session. Use the [`Participants.only(_:)`](/documentation/GroupActivities/Participants/only(_:)-swift.enum.case) option to specify a subset of participants. `completion` The handler block to call with the results of the delivery attempt. The handler has no return value and takes a single parameter. The value of this parameter is `nil` if delivery succeeds; otherwise, it contains an appropriate error object. ## Discussion Use this method to send data that you package into a custom class or structure. The method encodes your custom structure’s type information, and delivers the data only to message sequences of the same type. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)