diff --git a/testing-events.md b/testing-events.md
index a52e3f42..c7a0a6a8 100644
--- a/testing-events.md
+++ b/testing-events.md
@@ -16,7 +16,12 @@ Testing events covers the subjects and predicates related to test-execution perf
 
 ## Subjects
 
-This specification defines three subjects in this stage: `testCaseRun`, `testSuiteRun` and `testOutput`.
+This specification defines three subjects in this stage: `testCaseRun`, `testSuiteRun` and `testOutput`. When a producer sends `testCaseRun` or `testSuiteRun` messages, they should meet the following expectations:
+- a `queued` event may optionally be followed by a `started` event
+- a `queued` event must be followed by either a `started` or a `finished` event
+- a `finished` event following after a `queued` event without a `started` event in between, can only have its outcome set to `cancel` or `skip`
+- a `started` event must be followed by a `finished` event
+- a `finished` event may not be sent if no `queued` or `started` events are sent for the same subject
 
 | Subject                         | Description                                  | Predicates                                                                                                 |
 |---------------------------------|----------------------------------------------|------------------------------------------------------------------------------------------------------------|