diff --git a/lib/src/evaluator.dart b/lib/src/evaluator.dart
index a40984e..0f4c7bb 100644
--- a/lib/src/evaluator.dart
+++ b/lib/src/evaluator.dart
@@ -2,6 +2,7 @@ import 'package:liquify/parser.dart' show parseInput;
 import 'package:liquify/src/context.dart';
 import 'package:liquify/src/drop.dart';
 import 'package:liquify/src/tag_registry.dart';
+import 'package:liquify/src/util.dart';
 
 import 'ast.dart';
 import 'buffer.dart';
@@ -139,10 +140,10 @@ class Evaluator implements ASTVisitor<dynamic> {
         result = left >= right;
         break;
       case 'and':
-        result = left && right;
+        result = isTruthy(left) && isTruthy(right);
         break;
       case 'or':
-        result = left || right;
+        result = isTruthy(left) || isTruthy(right);
         break;
       case '..':
         result = List.generate(right - left + 1, (index) => left + index);
diff --git a/test/tags_test.dart b/test/tags_test.dart
index 329cb22..2a3d669 100644
--- a/test/tags_test.dart
+++ b/test/tags_test.dart
@@ -777,5 +777,53 @@ void main() {
         expect(evaluator.buffer.toString(), contains('not truthy'));
       });
     });
+
+    test('empty string', () {
+      testParser('''
+        {% assign name = "" %}
+        {% if name %}
+          truthy.
+        {% endif %}
+      ''', (document) {
+        evaluator.evaluate(document);
+        expect(evaluator.buffer.toString(), contains('truthy'));
+      });
+    });
+
+    test('null', () {
+      testParser('''
+        {% assign name = null %}
+        {% if name %}
+          truthy.
+        {% endif %}
+      ''', (document) {
+        evaluator.evaluate(document);
+        expect(evaluator.buffer.toString(), isNot(contains('truthy')));
+      });
+    });
+
+    test('binary operator and', () {
+      testParser('''
+        {% assign name = null %}
+        {% if name and "" %}
+          truthy.
+        {% endif %}
+      ''', (document) {
+        evaluator.evaluate(document);
+        expect(evaluator.buffer.toString(), isNot(contains('truthy')));
+      });
+    });
+
+    test('binary operator or', () {
+      testParser('''
+        {% assign name = null %}
+        {% if name or "" %}
+          truthy.
+        {% endif %}
+      ''', (document) {
+        evaluator.evaluate(document);
+        expect(evaluator.buffer.toString(), contains('truthy'));
+      });
+    });
   });
 }