# 3D Secure Sessions

A `3D Secure Session` represents one 3D Secure authentication that Finix runs on a card. Create the session, send the buyer through authentication, then reference the completed session when you create the [Transfer](/api/transfers) or [Authorization](/api/authorizations).

The `state` of a session describes the authentication process, not its outcome. A session where the buyer was never authenticated still ends in `SUCCEEDED`. To find out whether the buyer was authenticated, and where chargeback liability sits, read `3d_secure_authentication.electronic_commerce_indicator`.

**Related Guides:**
- [3D Secure](/guides/online-payments/fraud-and-risk/3d-secure)


## Create a 3D Secure Session

 - [POST /3d_secure_sessions](https://docs.finix.com/api/3d-secure-sessions/create3dsecuresession.md): Create a 3D Secure Session to authenticate a buyer before you charge their card.

Create the session from a payment_instrument_id for the redirect flow or standalone Finix.ThreeDSecure, or from a token_id for the ThreeDSecure payment form option. For redirect flows, pass the session ID after state reaches SUCCEEDED. With Finix.js, pass it when the succeeded callback fires, even if the session resource still reads PENDING.

## Fetch a 3D Secure Session

 - [GET /3d_secure_sessions/{3d_secure_session_id}](https://docs.finix.com/api/3d-secure-sessions/get3dsecuresession.md): Retrieve the details of a 3D Secure Session to check the state of the authentication and read the values the card network returned.