diff --git a/README.md b/README.md
index 5f1e59eb6..6fafa32a0 100644
--- a/README.md
+++ b/README.md
@@ -22,21 +22,21 @@ A generic event data model for future HEP collider experiments.
 
 | | | |
 |-|-|-|
-| [EventHeader](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L145)         | [MCParticle](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L155)        | [SimTrackerHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L224)         |
-| [CaloHitContribution](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L258) | [SimCalorimeterHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L270) | [RawCalorimeterHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L282)     |
-| [CalorimeterHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L291)      | [ParticleID](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L303)        | [Cluster](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L316)               |
-| [TrackerHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L337)          | [TrackerHitPlane](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L354)   | [RawTimeSeries](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L375)                |
-| [Track](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L388)               | [Vertex](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L407)            | [ReconstructedParticle](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L424) |
-| [SimPrimaryIonizationCluster](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L528) | [TrackerPulse](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L546) | [RecIonizationCluster](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L559) |
-| [TimeSeries](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L570) | [RecDqdx](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L582) |                                                                                          |
+| [EventHeader](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L145)         | [MCParticle](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L157)        | [SimTrackerHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L226)         |
+| [CaloHitContribution](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L260) | [SimCalorimeterHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L272) | [RawCalorimeterHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L284)     |
+| [CalorimeterHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L293)      | [ParticleID](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L305)        | [Cluster](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L318)               |
+| [TrackerHit](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L339)          | [TrackerHitPlane](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L356)   | [RawTimeSeries](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L377)                |
+| [Track](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L390)               | [Vertex](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L409)            | [ReconstructedParticle](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L426) |
+| [SimPrimaryIonizationCluster](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L530) | [TrackerPulse](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L548) | [RecIonizationCluster](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L561) |
+| [TimeSeries](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L572) | [RecDqdx](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L584) |                                                                                          |
 
 **Associations**
 
 | | | |
 |-|-|-|
-| [MCRecoParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L454)        | [MCRecoCaloAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L463)         | [MCRecoTrackerAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L472)         |
-| [MCRecoTrackerHitPlaneAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L481) | [MCRecoCaloParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L490) | [MCRecoClusterParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L499) |
-| [MCRecoTrackParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L508)   | [RecoParticleVertexAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L517) |                                                                                                      |
+| [MCRecoParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L456)        | [MCRecoCaloAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L465)         | [MCRecoTrackerAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L474)         |
+| [MCRecoTrackerHitPlaneAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L483) | [MCRecoCaloParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L492) | [MCRecoClusterParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L501) |
+| [MCRecoTrackParticleAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L510)   | [RecoParticleVertexAssociation](https://github.com/key4hep/EDM4hep/blob/main/edm4hep.yaml#L519) |                                                                                                      |
 
 The tests and examples in the `tests` directory show how to read, write, and use these types in your code.
 
diff --git a/edm4hep.yaml b/edm4hep.yaml
index 14cd2983f..1d60b2d24 100644
--- a/edm4hep.yaml
+++ b/edm4hep.yaml
@@ -150,6 +150,8 @@ datatypes:
       - int32_t runNumber      //run number
       - uint64_t timeStamp     //time stamp
       - float weight       // event weight
+    VectorMembers:
+      - double weights       // event weights in case there are multiple. **NOTE that weights[0] might not be the same as weight!** Event weight names should be stored using the edm4hep::EventWeights name in the file level metadata.
 
 
   edm4hep::MCParticle:
diff --git a/include/edm4hep/Constants.h b/include/edm4hep/Constants.h
index 48b09d6dc..81dde40ea 100644
--- a/include/edm4hep/Constants.h
+++ b/include/edm4hep/Constants.h
@@ -22,6 +22,7 @@
 namespace edm4hep {
 static constexpr const char* CellIDEncoding = "CellIDEncoding";
 static constexpr const char* EventHeaderName = "EventHeader";
+static constexpr const char* EventWeights = "EventWeightNames";
 } // namespace edm4hep
 
 #endif // EDM4HEP_CONSTANTS_H