| AdditionalInfos | A collection of additional information requests. |
 Comments | OTA formatted text typeAn indication of a new paragraph for a sub-section of a formatted text message. |
 Dates | A collection of dates which allows you to request preferred and/or alternate dates. |
| EventBlock | This is information pertaining to the event requirements for this request. |
| Histories | A collection of individual Histories. |
| Preferences | Collection of preferences or requirements for the RFP. |
| Profiles | This is who is submitting the request.A collection of Profile objects or Unique IDs of Profiles. |
| ProposalSpecification | Used to provide details on the proposal such as the key factors that will play a role in the proposal evaluation. |
| RFP_ID | This is a UniqueID that is associated with an individual RFP. This element repeats to accommodate the IDs of multiple systems. |
| RoomBlock | This is information pertaining to room requirements for this request. |
| Sites | A collection of sites for which the request is being submitted (e.g. a hotel, national sales office, convention center). |
| TPA_Extensions | A placeholder in the schema to allow for additional elements and attributes to be included per Trading Partner Agreement (TPA).Allows extensions to be added to the OpenTravel specification per trading partner agreement. |