diff --git a/pyproject.toml b/pyproject.toml
index 3e620c09..73c3ea42 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -14,7 +14,7 @@ dependencies = [
     "lxml>=4.9.3,<6.0.0",
     "openai>=1.11.0,<3.0.0",
     "rich>=13.6.0,<15.0.0",
-    "PettingZoo==1.25.0",
+    "PettingZoo==1.26.1",
     "redis-om>=0.3.0,<0.4.0",
     "gin-config>=0.5.0,<0.6.0",
     "json-repair>=0.35.0,<0.49.0",