diff --git a/contributors.py b/contributors.py
index f30ef5b..b1844dc 100755
--- a/contributors.py
+++ b/contributors.py
@@ -17,6 +17,9 @@
     if 'affiliations' in author:
         author["affiliations"] = [data["affiliations"][aff] for aff in author["affiliations"]]
 
+# Sort by last name and contribution tier
+data["authors"] = list(sorted(sorted(data["authors"], key=lambda x: x["lastName"]), key=lambda x: x.get("tier", 2)))
+
 env = jinja2.Environment(
    loader=jinja2.FileSystemLoader(os.getcwd()),
    keep_trailing_newline=True,
diff --git a/contributors.yml b/contributors.yml
index 77c5b38..4feebe2 100644
--- a/contributors.yml
+++ b/contributors.yml
@@ -22,6 +22,7 @@ authors:
     affiliations:
       - Institute for Modelling Hydraulic and Environmental Systems, University of Stuttgart, Germany
     orcid: 0000-0001-8188-620X
+    tier: 1
 
   - author: "Florian Goth"
     firstName: Florian
@@ -35,6 +36,7 @@ authors:
       FG acknowledges funding from the Deutsche Forschungsgemeinschaft
       (DFG, German Research Foundation) through the SFB 1170 “Tocotronics”,
       project Z03 - project number \href{https://gepris.dfg.de/gepris/projekt/258499086?language=en}{258499086}.
+    tier: 1
 
   - author: "Jean-Noël Grad"
     firstName: Jean-Noël
@@ -75,6 +77,7 @@ authors:
     acknowledgements: |
       DK acknowledges support from the Scientific Software Center which is funded as part
       of the Excellence Strategy of the German Federal and State Governments.
+    tier: 0
 
   - author: "Jan Linxweiler"
     firstName: Jan
@@ -84,6 +87,7 @@ authors:
       - Technische Universität Braunschweig, Germany
     orcid: 0000-0002-2755-5087
     email: j.linxweiler@tu-braunschweig.de
+    tier: 1
 
   - author: "Axel Loewe"
     firstName: Axel
@@ -102,6 +106,7 @@ authors:
       - Competence Center Digital Research, Friedrich Schiller University Jena, Germany
     orcid: 0000-0001-6643-6323
     email: frank.loeffler@uni-jena.de
+    tier: 1
 
   - author: "Philipp Matthias Schäfer"
     firstName: Philipp Matthias
@@ -111,6 +116,7 @@ authors:
       - Competence Center Digital Research, Friedrich Schiller University Jena, Germany
     orcid: 0000-0003-3931-6670
     email: philipp.matthias.schaefer@uni-jena.de
+    tier: 1
  
   - author: "Philipp S. Sommer"
     firstName: Philipp S.
@@ -125,6 +131,7 @@ authors:
       - Jülich Supercomputing Centre, Forschungszentrum Jülich GmbH, Germany
     orcid: 0000-0002-3879-1210
     email: r.speck@fz-juelich.de
+    tier: 1
 
   - author: "Alexander Struck"
     firstName: Alexander
@@ -136,4 +143,4 @@ authors:
     email: alexander.struck@hu-berlin.de
     acknowledgements: |
       AS acknowledges the support of the Cluster of Excellence »Matters of Activity. Image Space Material« funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany's Excellence Strategy – EXC 2025 – 390648296.
-
+    tier: 1