diff --git a/.coin-or/projDesc.xml b/.coin-or/projDesc.xml
index c55e023b548..0c8942ea955 100644
--- a/.coin-or/projDesc.xml
+++ b/.coin-or/projDesc.xml
@@ -227,8 +227,8 @@ Carl D. Laird, Chair, Pyomo Management Committee, claird at andrew dot cmu dot e
 			     Use explicit overrides to disable use of automated
 			     version reporting.
 			-->
-			<stableVersionNumber>6.6.0</stableVersionNumber>
-			<releaseNumber>6.6.0</releaseNumber>
+			<stableVersionNumber>6.6.1</stableVersionNumber>
+			<releaseNumber>6.6.1</releaseNumber>
 
 		</developmentStatus>
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 84d65a751ef..1bf751268fa 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,27 @@
 Pyomo CHANGELOG
 ===============
 
+
+-------------------------------------------------------------------------------
+Pyomo 6.6.1    (30 May 2023)
+-------------------------------------------------------------------------------
+
+- General
+  - Update cmake builder for recent setuptools (#2847)
+  - Fixing minor formatting for 6.6.0 release changes (#2842)
+  - Silence deprecation warnings (#2854)
+- Core
+  - Update indentation handling in `config.StringFormatter` (#2853)
+  - Restore slice API broken by #2829 (#2849)
+  - Resolve handling of {}**0 in `LinearRepn`/`QuadraticRepn` (#2857)
+- Solver Interfaces
+  - NL writer: resolve error identifying vars in indexed SOS (#2852)
+  - Manage Gurobi environments in GurobiDirect (#2680)
+- Contributed Packages
+  - cp: fix handling fixed BooleanVars in logical-to-disjunctive walker (#2850)
+  - FBBT: Fix typo when handling GeneralExpression objects (#2848)
+  - MindtPy: add support for cyipopt (#2830)
+
 -------------------------------------------------------------------------------
 Pyomo 6.6.0    (24 May 2023)
 -------------------------------------------------------------------------------
diff --git a/RELEASE.md b/RELEASE.md
index 6f34462774e..53de39654c9 100644
--- a/RELEASE.md
+++ b/RELEASE.md
@@ -1,4 +1,4 @@
-We are pleased to announce the release of Pyomo 6.6.0.
+We are pleased to announce the release of Pyomo 6.6.1.
 
 Pyomo is a collection of Python software packages that supports a
 diverse set of optimization capabilities for formulating and analyzing
diff --git a/pyomo/version/info.py b/pyomo/version/info.py
index 5d182e3ae77..fdddc3f49e4 100644
--- a/pyomo/version/info.py
+++ b/pyomo/version/info.py
@@ -27,8 +27,8 @@
 major = 6
 minor = 6
 micro = 1
-releaselevel = 'invalid'
-# releaselevel = 'final'
+# releaselevel = 'invalid'
+releaselevel = 'final'
 serial = 0
 
 if releaselevel == 'final':
diff --git a/setup.py b/setup.py
index ec41c38f115..071893a7ad3 100644
--- a/setup.py
+++ b/setup.py
@@ -264,9 +264,8 @@ def _print_deps(self, deplist):
             # install on PyPy (binary wheels are not available), so we
             # will only "require" them on other (CPython) platforms:
             #
-            # DAE can use casadi; as of 1 Nov 22, casadi has not been
-            # released for Python 3.11
-            'casadi; implementation_name!="pypy" and python_version<"3.11"',
+            # DAE can use casadi
+            'casadi; implementation_name!="pypy"',
             'numdifftools; implementation_name!="pypy"',  # pynumero
             'pandas; implementation_name!="pypy"',
             'seaborn; implementation_name!="pypy"',  # parmest.graphics