diff --git a/provider/README.md b/provider/README.md
index 1591e984..257a6d19 100644
--- a/provider/README.md
+++ b/provider/README.md
@@ -125,6 +125,7 @@ Response: See the [`trips` schema][trips-schema] for the expected format.
 | `trip_duration` | Integer | Required | Time, in Seconds |
 | `trip_distance` | Integer | Required | Trip Distance, in Meters |
 | `route` | GeoJSON `FeatureCollection` | Required | See [Routes](#routes) detail below |
+| `access_method` | Enum | Required | An [access method](#access-methods): how the user gained access to the vehicle |
 | `accuracy` | Integer | Required | The approximate level of accuracy, in meters, of `Points` within `route` |
 | `start_time` | [timestamp][ts] | Required | |
 | `end_time` | [timestamp][ts] | Required | |
@@ -206,6 +207,25 @@ Routes must include at least 2 points: the start point and end point. Additional
 }
 ```
 
+### Access methods
+
+| `access_method` | meaning                                                                        |
+|-----------------|--------------------------------------------------------------------------------|
+| `qr_code`       | The user scanned a QR code with their mobile device                            |
+| `keypad`        | The user entered an identification number on a keypad                          |
+| `transit_card`  | The user used a transit card to unlock the vehicle                             |
+| `rfid`          | The user accessed the vehicle with an RFID card or fob that is not a transit card |
+| `mobile_id`     | The user entered the ID of the device on their mobile phone                    |
+| `other_mobile`  | The user used a mobile phone, but did not scan a QR code or enter a vehicle ID |
+| `credit_card_pay`   | The user swiped/inserted/tapped their credit card to pay for the ride      |
+| `credit_card_id`    | The user swiped/inserted/tapped their credit card to identify themselves, but their card was not charged an additional amount |
+| `cash_attendant` | The user paid an attendant or operator cash to use the vehicle                |
+| `cash_automated` | The user paid cash using an automated system                                  |
+| `call_center`    | The user accessed the vehicle by calling a call center operated by humans     |
+| `ivr`            | An interactive voice response system was used to access the vehicle           |
+| `sms`            | An SMS system was used to access the vehicle                                  |
+| `no_security`    | The vehicles are unsecured and can be used by anyone without charge           |
+
 [Top][toc]
 
 ## Status Changes
@@ -239,7 +259,7 @@ The status_changes API should allow querying status changes with a combination o
 
 * `start_time`: filters for status changes where `event_time` occurs at or after the given time
 * `end_time`: filters for status changes where `event_time` occurs at or before the given time
-* `bbox`: filters for status changes where `event_location` is within defined bounding-box. The order is definied as: southwest longitude, southwest latitude, northeast longitude, northeast latitude (separated by commas). 
+* `bbox`: filters for status changes where `event_location` is within defined bounding-box. The order is definied as: southwest longitude, southwest latitude, northeast longitude, northeast latitude (separated by commas).
 
 Example: