[Profiles & Operations](https://simplifier.net/guide/eReferralOntario/ProfilesandOperations) > Profile: Bundle
## Profile: Bundle
Bundle is used to group collection of resources together.
### Legend
* Must Support= **True** indicates the element included in this profile are the only one supported by this specification
* `red` indicates that the field is likely useful in a future iteration of the specification
##### Canonical URl for this profile: http://fhir.infoway-inforoute.ca/StructureDefinition/ca-eReferral-bundle
| Name | Card | Must Support | Type | Comments |
|---|---|---|---|
|identifier| 0..*| | Identifier~ | |
| type | 1..1 | True | code | always sent as "transaction", responses are "transaction-response"
| timestamp | 0..1 | True | instant | The time when the bundle was created by the transmitter. |
| total | 0..1 | True | unsignedInt | If search, the total number of matches. Otherwise not used.
| `link` | 0..1 | True | BackboneElement | `for future use` used to support paging functions
| `link.relation` | 1..1 | True | string | `for future use`
| `link.url` | 1..1 | True | url | `for future use`
| entry | 0..* | True | BackboneElement |
| `entry.link` | 0..* | True | link | `for future use`
| entry.fullUrl | 0..1 | True | url |
| entry.resource | 0..1 | True | Resource | Holds each resource in the bundle
| `entry.search` | 0..1 | True | BackboneElementnt | `for future use`
| `entry.search.mode` | 0..1 | True |code | `for future use`
| `entry.search.score` | 0..1 | True | decimal | `for future use`
| entry.request | 0..1 | True | BackboneElement |
| entry.request.method | 1..1 | True | code | POST for new resources. PUT for updates. GET to retrieve resources. HEAD \ DELETE \ PATCH not supported
| entry.request.url | 1..1 | True | code | URL for HTTP equivalent of this entry
| `entry.request.ifNoneMatch` | 0..1 | True | string | `for future use`
| `entry.request.ifModifiedSince` | 0..1 | True | instant | `for future use`
| `entry.request.ifMatch` | 0..1 | True | string | `for future use`
| `entry.request.ifNoneExist` | 0..1 | True | string | `for future use`
| response | 0..1 | True | BackboneElement | Transaction Related Information
| response.status | 1..1 | True | string | Status response code (text optional)
| response.location | 0..1 | True | uri | The location, if the operation returns a location
| response.etag | 0..1 | True | string | The etag for the resource (if relevant)
| response.lastModified | 0..1 | True | instant | server's date time modified
| response.outcome | 0..1 | True | Resource | OperationOutcome with hints and warnings (for batch/transaction)
| `signature` | 0..1 | True | Signature | `for future use`
One common operation performed with resources is to gather a collection of resources into a single instance with containing context. In FHIR this is referred to as "bundling" the resources together. These resource bundles are useful for a variety of different reasons, including:
1. Returning a set of resources that meet some criteria as part of a server operation
2. Returning a set of versions of resources as part of the history operation on a server
3. Sending a set of resources as part of a message exchange
4. Grouping a self-contained set of resources to act as an exchangeable and persistable collection with clinical integrity - e.g. a clinical document
5. Creating/updating/deleting a set of resources on a server as a single operation (including doing so as a single atomic transaction)
6. Storing a collection of resources
In this eReferral specificaiton, ServicesRequest resources are sent in a bundle with all of the relevant resources (patient, practitioner, organization, etc...). Thus, the eReferral specification applies scenario 4) & 5 listed above.