diff --git a/teams/sig_standard_cert/onetimes.yml b/teams/sig_standard_cert/onetimes.yml
index 023e2b6..2b090c1 100644
--- a/teams/sig_standard_cert/onetimes.yml
+++ b/teams/sig_standard_cert/onetimes.yml
@@ -15,3 +15,22 @@ events:
       Jitsi server on https://conf.scs.koeln:8443/SCS-Tech
       Dial-In: +49-221-292772-611
       Coordinator: Matthias Büchse <matthias.buechse[at]cloudandheat.com>
+
+  - summary: "SIG Standardization/Certification: extra session"
+    begin: 2026-06-25 14:05:00
+    uid: sig-std-crt-2026-06-25@docs.scs.community
+    duration:
+      minutes: 50
+    description: |
+      In this Special Interest Group, we discuss and align our activities and approach to standardization and certification. That is to say, we devise and refine the relevant concepts and processes; we work on a roadmap for new certificate versions; and we align on which standards are desireable for each certificate subject. We then work with the teams to align on existing or new standards.
+
+      Besides aspects of openness and sovereignty, the main goal of our standards is interoperability. We should take the user perspective: As a member of a DevOps team developing a service (think SaaS or PaaS) for SCS, I need XYZ. Every standard should be abstract enough to work regardless of the SCS reference implementation.
+
+      This SIG is a joint effort by SCS and ALASCA.
+
+      Minutes: https://github.com/SovereignCloudStack/minutes/tree/main/sig-standardization
+      HedgeDoc: https://input.scs.community/2026-scs-sig-standardization
+      Jitsi server on https://conf.scs.koeln:8443/SCS-Tech
+      Dial-In: +49-221-292772-611
+      Coordinator: Matthias Büchse <matthias.buechse[at]alasca.cloud>
+    location: "https://conf.scs.koeln:8443/SCS-Tech"