diff --git a/libraries/AdaptiveExpressions/BuiltinFunctions/Bool.cs b/libraries/AdaptiveExpressions/BuiltinFunctions/Bool.cs
index c57e732849..7ed30c7fbb 100644
--- a/libraries/AdaptiveExpressions/BuiltinFunctions/Bool.cs
+++ b/libraries/AdaptiveExpressions/BuiltinFunctions/Bool.cs
@@ -1,7 +1,9 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System;
 using System.Collections.Generic;
+using System.Globalization;
 
 namespace AdaptiveExpressions.BuiltinFunctions
 {
@@ -29,6 +31,18 @@ private static bool Function(IReadOnlyList<object> args)
                 arg = @int != 0;
             }
 
+            if (arg is string @string)
+            {
+                try
+                {
+                    arg = Convert.ToBoolean(@string, CultureInfo.InvariantCulture);
+                }
+                catch (FormatException)
+                {
+                    // Any string other than 'true' or 'false' will throw an exception. We'll ignore them.
+                }
+            }
+
             return FunctionUtils.IsLogicTrue(arg);
         }
     }
diff --git a/tests/AdaptiveExpressions.Tests/ExpressionParserTests.cs b/tests/AdaptiveExpressions.Tests/ExpressionParserTests.cs
index b33267a716..ef909760e0 100644
--- a/tests/AdaptiveExpressions.Tests/ExpressionParserTests.cs
+++ b/tests/AdaptiveExpressions.Tests/ExpressionParserTests.cs
@@ -734,7 +734,8 @@ public class ExpressionParserTests
             Test("bool(0)", false),
             Test("bool(null)", false),
             Test("bool(hello * 5)", false),
-            Test("bool('false')", true),
+            Test("bool('false')", false),
+            Test("bool('true')", true),
             Test("bool('hi')", true),
             Test("[1,2,3]", new List<object> { 1, 2, 3 }),
             Test("[1,2,3, [4,5]]", new List<object> { 1, 2, 3, new List<object> { 4, 5 } }),