## Conference calls

The Sinch dashboard supports a variety of different ways of initiating a conference call and connecting participants.

By using the Sinch Voice SDKs, you can allow your users to call in a conference from a mobile or web app. For more information please check the Voice SDKs documentation.

If you haven't specified a callback URL under your app settings for voice, the participants will be directly added to the conference that's uniquely identified by the conference ID specified in the SDK client method.

If you have specified a callback URL under your app settings for voice, an *Incoming Call Event* callback will be triggered towards your URL, containing information on the conference ID that the caller wants to connect to. By responding to this event you can allow or deny the connection to the conference, or even specify a different conference ID.

You can also allow users to dial in a conference by calling a fixed phone number. To do this, first follow the steps mentioned in [Phone to phone calls](https://developers.sinch.com/docs/voice/api-reference/voice/section/api-overview/callback-api#section/api-overview/Phone-to-phone-calls) to configure a number in your app and set a callback URL. Every time a user calls your configured number, an *Incoming Call Event* callback will be triggered towards your URL. By responding to this event with the `ConnectConf` action, you can connect the call to a conference.

For more information check the [Incoming Call Event](https://developers.sinch.com/docs/voice/api-reference/voice/callbacks/ice) callback and the [ConnectConf](https://developers.sinch.com/docs/voice/api-reference/svaml/actions#connectconf) action.

By using the conference callout endpoint, you can trigger calls to fixed or mobile phones and connect them all to the same conference room.

The Voice API allows you to control an ongoing conference. There are several conference-control options available, such as muting/unmuting participants or kicking out a participant or all participants from the conference when the conference ends.

The Voice API also allows recording of conference calls. For more information on how to record a conference, please check the `ConnectConf` action in the [SVAML Actions](https://developers.sinch.com/docs/voice/api-reference/svaml/actions#connectconf) page.

Important!
Conference rooms have regional scope. If you want to connect multiple participants from different regions (Continents) on the same conference, you must “force” all members to be on the same region.

This can be done by selecting the same Sinch [Voice API regional endpoints](https://developers.sinch.com/docs/voice/api-reference/voice/section/api-overview/endpoints) for Callout requests and/or the Sinch [In-App regional endpoint/hostname](https://developers.sinch.com/docs/in-app-calling/overview/#sinch-in-app-global--regional-hostnamesendpoints) to be used on your Mobile or Web Apps.