diff --git a/docs/test_cases.md b/docs/test_cases.md
index e4da3ba2..c4a69690 100644
--- a/docs/test_cases.md
+++ b/docs/test_cases.md
@@ -25,6 +25,7 @@
  * [t00024](./test_cases/t00024.md) - Proxy pattern
  * [t00025](./test_cases/t00025.md) - Template proxy pattern
  * [t00026](./test_cases/t00026.md) - Template memento pattern
+ * [t00027](./test_cases/t00027.md) - Template decorator pattern
 ## Sequence diagrams
  * [t20001](./test_cases/t20001.md) - Basic sequence diagram
 ## Configuration diagrams
diff --git a/docs/test_cases/t00026.md b/docs/test_cases/t00026.md
index fece16cc..f0012b02 100644
--- a/docs/test_cases/t00026.md
+++ b/docs/test_cases/t00026.md
@@ -74,7 +74,6 @@ struct StringMemento {
     Caretaker<std::string> caretaker;
     Originator<std::string> originator;
 };
-
 }
 }
 
diff --git a/docs/test_cases/t00027.md b/docs/test_cases/t00027.md
new file mode 100644
index 00000000..b794cfe3
--- /dev/null
+++ b/docs/test_cases/t00027.md
@@ -0,0 +1,79 @@
+# t00027 - Template decorator pattern
+## Config
+```yaml
+compilation_database_dir: ..
+output_directory: puml
+diagrams:
+  t00027_class:
+    type: class
+    glob:
+      - ../../tests/t00027/t00027.cc
+    using_namespace:
+      - clanguml::t00027
+    include:
+      namespaces:
+        - clanguml::t00027
+
+```
+## Source code
+File t00027.cc
+```cpp
+#include <memory>
+#include <tuple>
+#include <type_traits>
+
+namespace clanguml {
+namespace t00027 {
+
+class Shape {
+public:
+    virtual void display() = 0;
+    virtual ~Shape() = default;
+};
+
+template <template <typename> class... T>
+class Line : public Shape, public T<Line<>>... {
+public:
+    void display() override
+    {
+        std::apply([](auto &&... x) { (x.display(), ...); },
+            std::forward_as_tuple(T<Line<>>()...));
+    }
+};
+
+template <template <typename> class... T>
+class Text : public Shape, public T<Text<>>... {
+public:
+    void display() override
+    {
+        std::apply([](auto &&... x) { (x.display(), ...); },
+            std::forward_as_tuple(T<Text<>>()...));
+    }
+};
+
+struct ShapeDecorator {
+    virtual void display() = 0;
+};
+
+template <typename T> class Color : public ShapeDecorator {
+public:
+    void display() override {}
+};
+
+template <typename T> class Weight : public ShapeDecorator {
+public:
+    void display() override {}
+};
+
+struct Window {
+    Line<Color, Weight> border;
+    Line<Color> divider;
+    Text<Color, Weight> title;
+    Text<Color> description;
+};
+}
+}
+
+```
+## Generated UML diagrams
+![t00027_class](./t00027_class.png "Template decorator pattern")
diff --git a/docs/test_cases/t00027_class.png b/docs/test_cases/t00027_class.png
new file mode 100644
index 00000000..627f9562
Binary files /dev/null and b/docs/test_cases/t00027_class.png differ
diff --git a/src/puml/class_diagram_generator.h b/src/puml/class_diagram_generator.h
index c4625334..9acbd718 100644
--- a/src/puml/class_diagram_generator.h
+++ b/src/puml/class_diagram_generator.h
@@ -271,7 +271,8 @@ public:
                 try {
                     relstr << m_model.to_alias(uns, ns_relative(uns, b.name))
                            << " <|-- "
-                           << m_model.to_alias(uns, ns_relative(uns, c.name))
+                           << m_model.to_alias(
+                                  uns, ns_relative(uns, c.full_name(uns)))
                            << std::endl;
                     ostr << relstr.str();
                 }
diff --git a/src/uml/class_diagram_visitor.cc b/src/uml/class_diagram_visitor.cc
index 277f980d..b129b325 100644
--- a/src/uml/class_diagram_visitor.cc
+++ b/src/uml/class_diagram_visitor.cc
@@ -319,6 +319,8 @@ void tu_visitor::process_class_declaration(const cppast::cpp_class &cls,
             cp.access = class_parent::access_t::kPublic;
         }
 
+        LOG_DBG("Found base class {} for class {}", cp.name, c.name);
+
         c.bases.emplace_back(std::move(cp));
     }
 
diff --git a/tests/t00027/.clanguml b/tests/t00027/.clanguml
new file mode 100644
index 00000000..27103b8e
--- /dev/null
+++ b/tests/t00027/.clanguml
@@ -0,0 +1,12 @@
+compilation_database_dir: ..
+output_directory: puml
+diagrams:
+  t00027_class:
+    type: class
+    glob:
+      - ../../tests/t00027/t00027.cc
+    using_namespace:
+      - clanguml::t00027
+    include:
+      namespaces:
+        - clanguml::t00027
diff --git a/tests/t00027/t00027.cc b/tests/t00027/t00027.cc
new file mode 100644
index 00000000..379a100d
--- /dev/null
+++ b/tests/t00027/t00027.cc
@@ -0,0 +1,55 @@
+#include <memory>
+#include <tuple>
+#include <type_traits>
+
+namespace clanguml {
+namespace t00027 {
+
+class Shape {
+public:
+    virtual void display() = 0;
+    virtual ~Shape() = default;
+};
+
+template <template <typename> class... T>
+class Line : public Shape, public T<Line<>>... {
+public:
+    void display() override
+    {
+        std::apply([](auto &&... x) { (x.display(), ...); },
+            std::forward_as_tuple(T<Line<>>()...));
+    }
+};
+
+template <template <typename> class... T>
+class Text : public Shape, public T<Text<>>... {
+public:
+    void display() override
+    {
+        std::apply([](auto &&... x) { (x.display(), ...); },
+            std::forward_as_tuple(T<Text<>>()...));
+    }
+};
+
+struct ShapeDecorator {
+    virtual void display() = 0;
+};
+
+template <typename T> class Color : public ShapeDecorator {
+public:
+    void display() override {}
+};
+
+template <typename T> class Weight : public ShapeDecorator {
+public:
+    void display() override {}
+};
+
+struct Window {
+    Line<Color, Weight> border;
+    Line<Color> divider;
+    Text<Color, Weight> title;
+    Text<Color> description;
+};
+}
+}
diff --git a/tests/t00027/test_case.h b/tests/t00027/test_case.h
new file mode 100644
index 00000000..7f04ae86
--- /dev/null
+++ b/tests/t00027/test_case.h
@@ -0,0 +1,66 @@
+/**
+ * tests/t00027/test_case.cc
+ *
+ * Copyright (c) 2021 Bartek Kryza <bkryza@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+TEST_CASE("t00027", "[test-case][class]")
+{
+    auto [config, db] = load_config("t00027");
+
+    auto diagram = config.diagrams["t00027_class"];
+
+    REQUIRE(diagram->name == "t00027_class");
+
+    REQUIRE(diagram->include.namespaces.size() == 1);
+    REQUIRE_THAT(diagram->include.namespaces,
+        VectorContains(std::string{"clanguml::t00027"}));
+
+    REQUIRE(diagram->exclude.namespaces.size() == 0);
+
+    REQUIRE(diagram->should_include("clanguml::t00027::A"));
+
+    auto model = generate_class_diagram(db, diagram);
+
+    REQUIRE(model.name == "t00027_class");
+
+    auto puml = generate_class_puml(diagram, model);
+    AliasMatcher _A(puml);
+
+    REQUIRE_THAT(puml, StartsWith("@startuml"));
+    REQUIRE_THAT(puml, EndsWith("@enduml\n"));
+    REQUIRE_THAT(puml, IsAbstractClass(_A("Shape")));
+    REQUIRE_THAT(puml, IsAbstractClass(_A("ShapeDecorator")));
+    REQUIRE_THAT(puml, IsClassTemplate("Line", "T<>"));
+    REQUIRE_THAT(puml, IsClassTemplate("Text", "T<>"));
+    REQUIRE_THAT(puml, IsInstantiation(_A("Line<T<>>"), _A("Line<Color>")));
+    REQUIRE_THAT(
+        puml, IsInstantiation(_A("Line<T<>>"), _A("Line<Color,Weight>")));
+    REQUIRE_THAT(puml, IsInstantiation(_A("Text<T<>>"), _A("Text<Color>")));
+    REQUIRE_THAT(
+        puml, IsInstantiation(_A("Text<T<>>"), _A("Text<Color,Weight>")));
+
+    REQUIRE_THAT(
+        puml, IsAggregation(_A("Window"), _A("Line<Color,Weight>"), "+border"));
+    REQUIRE_THAT(
+        puml, IsAggregation(_A("Window"), _A("Line<Color>"), "+divider"));
+    REQUIRE_THAT(
+        puml, IsAggregation(_A("Window"), _A("Text<Color,Weight>"), "+title"));
+    REQUIRE_THAT(
+        puml, IsAggregation(_A("Window"), _A("Text<Color>"), "+description"));
+
+    save_puml(
+        "./" + config.output_directory + "/" + diagram->name + ".puml", puml);
+}
diff --git a/tests/test_cases.cc b/tests/test_cases.cc
index c2140124..a7733757 100644
--- a/tests/test_cases.cc
+++ b/tests/test_cases.cc
@@ -130,6 +130,7 @@ using namespace clanguml::test::matchers;
 #include "t00024/test_case.h"
 #include "t00025/test_case.h"
 #include "t00026/test_case.h"
+#include "t00027/test_case.h"
 
 //
 // Sequence diagram tests
diff --git a/tests/test_cases.yaml b/tests/test_cases.yaml
index 72ab5a2f..dcf4f62a 100644
--- a/tests/test_cases.yaml
+++ b/tests/test_cases.yaml
@@ -75,6 +75,9 @@ test_cases:
     - name: t00026
       title: Template memento pattern
       description:
+    - name: t00027
+      title: Template decorator pattern
+      description:
   Sequence diagrams:
     - name: t20001
       title: Basic sequence diagram