diff --git a/data/bitclust/template/class b/data/bitclust/template/class
index b4f3afbb..d179183b 100644
--- a/data/bitclust/template/class
+++ b/data/bitclust/template/class
@@ -30,6 +30,20 @@
 <% unless @entry.aliases.empty? %>
 <br>aliases: <%=h @entry.aliases.map{|c| c.name}.join(', ') %>
 <% end %>
+<% unless @entry.dynamically_included.empty? %>
+<br> dynamic include:
+ <%= @entry.dynamically_included.map{|m| 
+       class_link(m.name) + " (by " + library_link(m.library.name) + ")"
+     }.join(", ")
+ %>
+<% end %>
+<% unless @entry.dynamically_extended.empty? %>
+<br> dynamic extend:
+ <%= @entry.dynamically_extended.map{|m| 
+       class_link(m.name) + " (by " + library_link(m.library.name) + ")"
+     }.join(", ")
+ %>
+<% end %>
 </p>
 <%
     headline_push
diff --git a/lib/bitclust/classentry.rb b/lib/bitclust/classentry.rb
index 554d9e29..6dc6b034 100644
--- a/lib/bitclust/classentry.rb
+++ b/lib/bitclust/classentry.rb
@@ -81,6 +81,8 @@ def labels
       property :superclass, 'ClassEntry'
       property :included,   '[ClassEntry]'
       property :extended,   '[ClassEntry]'
+      property :dynamically_included, '[ClassEntry]'
+      property :dynamically_extended, '[ClassEntry]'
       property :library,    'LibraryEntry'
       property :aliases,    '[ClassEntry]'
       property :aliasof,    'ClassEntry'
@@ -142,6 +144,24 @@ def extend(m)
       extended().push m
     end
 
+    # Add a module +m+ to the dynamically included module list.
+    def dynamic_include(m, lib)
+      if m.library != lib
+        message = "dynamically included module #{m.name} should be defined in the module #{lib.name}"
+        raise InvalidLibrary, message
+      end
+      dynamically_included().push m
+    end
+
+    # Add a module +m+ to the dynamically extended module list.
+    def dynamic_extend(m, lib)
+      if m.library != lib
+        message = "dynamically extended module #{m.name} should be defined in the module #{lib.name}"
+        raise InvalidLibrary, message
+      end
+      dynamically_extended().push m
+    end
+
     # Add a alias +c+ to the alias list.
     def alias(c)
       aliases().push c
diff --git a/lib/bitclust/exception.rb b/lib/bitclust/exception.rb
index 5e069f24..33b023d1 100644
--- a/lib/bitclust/exception.rb
+++ b/lib/bitclust/exception.rb
@@ -17,6 +17,7 @@ class ParseError              < DocumentError; end
   class WrongInclude            < DocumentError; end
   class InvalidLink             < DocumentError; end
   class InvalidAncestor         < DocumentError; end
+  class InvalidLibrary          < DocumentError; end
   class UserError               < Error; end
   class InvalidDatabase         < UserError; end
   class InvalidKey              < UserError; end
diff --git a/lib/bitclust/rrdparser.rb b/lib/bitclust/rrdparser.rb
index adb398f9..0695fbe1 100644
--- a/lib/bitclust/rrdparser.rb
+++ b/lib/bitclust/rrdparser.rb
@@ -194,15 +194,21 @@ def read_aliases(f)
 
     def read_includes(f, reopen = false)
       f.while_match(/\Ainclude\s/) do |line|
-        tty_warn "#{line.location}: dynamic include is not implemented yet" if reopen
-        @context.include line.split[1]          unless reopen # FIXME
+        if reopen
+          @context.dynamic_include(line.split[1])
+        else
+          @context.include(line.split[1])
+        end
       end
     end
 
     def read_extends(f, reopen = false)
       f.while_match(/\Aextend\s/) do |line|
-        tty_warn "#{line.location}: dynamic extend is not implemented yet" if reopen
-        @context.extend line.split[1]           unless reopen # FIXME
+        if reopen
+          @context.dynamic_extend(line.split[1])
+        else
+          @context.extend(line.split[1])
+        end
       end
     end
 
@@ -403,6 +409,14 @@ def extend(name)
         @klass.extend @db.get_class(name)
       end
 
+      def dynamic_include(name)
+        @klass.dynamic_include(@db.get_class(name), @library)
+      end
+
+      def dynamic_extend(name)
+        @klass.dynamic_extend(@db.get_class(name), @library)
+      end
+
       # Add a alias +name+ to the alias list.
       def alias(name)
         @db.open_class(name) do |c|
diff --git a/test/test_methoddatabase.rb b/test/test_methoddatabase.rb
index 4546a94e..ba5a3b48 100644
--- a/test/test_methoddatabase.rb
+++ b/test/test_methoddatabase.rb
@@ -50,12 +50,25 @@ def test_search_methods__constant
     assert_equal 'AAA', result.records.first.entry.name
   end
 
+  def test_dynamic_include
+    assert_equal(["BazA"],
+                 @db.get_class("A").dynamically_included.map{|m| m.name})
+    assert_equal(["BazB"],
+                 @db.get_class("B").dynamically_included.map{|m| m.name})
+  end
+
   private
   def setup_files
     FileUtils.mkdir_p("#{@root}/_builtin")
+
     File.open("#{@root}/LIBRARIES", 'w+') do |file|
       file.puts '_builtin'
+      file.puts 'dyn_include_open_a'
+      file.puts 'dyn_include_reopen_a'
+      file.puts 'dyn_include_reopen_b'
+      file.puts 'dyn_include_open_b'
     end
+
     File.open("#{@root}/_builtin.rd", 'w+') do |file|
       file.puts <<'HERE'
 description
@@ -77,5 +90,25 @@ def setup_files
 
 HERE
     end
+
+    File.open("#{@root}/dyn_include_open_a.rd", 'w+') do |file|
+      file.puts "= class A"
+    end
+
+    File.open("#{@root}/dyn_include_reopen_a.rd", 'w+') do |file|
+      file.puts "= module BazA"
+      file.puts "= reopen A"
+      file.puts "include BazA"
+    end
+
+    File.open("#{@root}/dyn_include_open_b.rd", 'w+') do |file|
+      file.puts "= class B"
+    end
+
+    File.open("#{@root}/dyn_include_reopen_b.rd", 'w+') do |file|
+      file.puts "= module BazB"
+      file.puts "= reopen B"
+      file.puts "include BazB"
+    end
   end
 end