diff --git a/doc/argument_converters.rdoc b/doc/optparse/argument_converters.rdoc
similarity index 100%
rename from doc/argument_converters.rdoc
rename to doc/optparse/argument_converters.rdoc
diff --git a/doc/creates_option.rdoc b/doc/optparse/creates_option.rdoc
similarity index 100%
rename from doc/creates_option.rdoc
rename to doc/optparse/creates_option.rdoc
diff --git a/doc/option_params.rdoc b/doc/optparse/option_params.rdoc
similarity index 100%
rename from doc/option_params.rdoc
rename to doc/optparse/option_params.rdoc
diff --git a/doc/ruby/abbreviation.rb b/doc/optparse/ruby/abbreviation.rb
similarity index 100%
rename from doc/ruby/abbreviation.rb
rename to doc/optparse/ruby/abbreviation.rb
diff --git a/doc/ruby/argument_keywords.rb b/doc/optparse/ruby/argument_keywords.rb
similarity index 100%
rename from doc/ruby/argument_keywords.rb
rename to doc/optparse/ruby/argument_keywords.rb
diff --git a/doc/ruby/argument_strings.rb b/doc/optparse/ruby/argument_strings.rb
similarity index 100%
rename from doc/ruby/argument_strings.rb
rename to doc/optparse/ruby/argument_strings.rb
diff --git a/doc/ruby/argv.rb b/doc/optparse/ruby/argv.rb
similarity index 100%
rename from doc/ruby/argv.rb
rename to doc/optparse/ruby/argv.rb
diff --git a/doc/ruby/array.rb b/doc/optparse/ruby/array.rb
similarity index 100%
rename from doc/ruby/array.rb
rename to doc/optparse/ruby/array.rb
diff --git a/doc/ruby/block.rb b/doc/optparse/ruby/block.rb
similarity index 100%
rename from doc/ruby/block.rb
rename to doc/optparse/ruby/block.rb
diff --git a/doc/ruby/collected_options.rb b/doc/optparse/ruby/collected_options.rb
similarity index 100%
rename from doc/ruby/collected_options.rb
rename to doc/optparse/ruby/collected_options.rb
diff --git a/doc/ruby/custom_converter.rb b/doc/optparse/ruby/custom_converter.rb
similarity index 100%
rename from doc/ruby/custom_converter.rb
rename to doc/optparse/ruby/custom_converter.rb
diff --git a/doc/ruby/date.rb b/doc/optparse/ruby/date.rb
similarity index 100%
rename from doc/ruby/date.rb
rename to doc/optparse/ruby/date.rb
diff --git a/doc/ruby/datetime.rb b/doc/optparse/ruby/datetime.rb
similarity index 100%
rename from doc/ruby/datetime.rb
rename to doc/optparse/ruby/datetime.rb
diff --git a/doc/ruby/decimal_integer.rb b/doc/optparse/ruby/decimal_integer.rb
similarity index 100%
rename from doc/ruby/decimal_integer.rb
rename to doc/optparse/ruby/decimal_integer.rb
diff --git a/doc/ruby/decimal_numeric.rb b/doc/optparse/ruby/decimal_numeric.rb
similarity index 100%
rename from doc/ruby/decimal_numeric.rb
rename to doc/optparse/ruby/decimal_numeric.rb
diff --git a/doc/ruby/default_values.rb b/doc/optparse/ruby/default_values.rb
similarity index 100%
rename from doc/ruby/default_values.rb
rename to doc/optparse/ruby/default_values.rb
diff --git a/doc/ruby/descriptions.rb b/doc/optparse/ruby/descriptions.rb
similarity index 100%
rename from doc/ruby/descriptions.rb
rename to doc/optparse/ruby/descriptions.rb
diff --git a/doc/ruby/explicit_array_values.rb b/doc/optparse/ruby/explicit_array_values.rb
similarity index 100%
rename from doc/ruby/explicit_array_values.rb
rename to doc/optparse/ruby/explicit_array_values.rb
diff --git a/doc/ruby/explicit_hash_values.rb b/doc/optparse/ruby/explicit_hash_values.rb
similarity index 100%
rename from doc/ruby/explicit_hash_values.rb
rename to doc/optparse/ruby/explicit_hash_values.rb
diff --git a/doc/ruby/false_class.rb b/doc/optparse/ruby/false_class.rb
similarity index 100%
rename from doc/ruby/false_class.rb
rename to doc/optparse/ruby/false_class.rb
diff --git a/doc/ruby/float.rb b/doc/optparse/ruby/float.rb
similarity index 100%
rename from doc/ruby/float.rb
rename to doc/optparse/ruby/float.rb
diff --git a/doc/ruby/integer.rb b/doc/optparse/ruby/integer.rb
similarity index 100%
rename from doc/ruby/integer.rb
rename to doc/optparse/ruby/integer.rb
diff --git a/doc/ruby/long_names.rb b/doc/optparse/ruby/long_names.rb
similarity index 100%
rename from doc/ruby/long_names.rb
rename to doc/optparse/ruby/long_names.rb
diff --git a/doc/ruby/long_optional.rb b/doc/optparse/ruby/long_optional.rb
similarity index 100%
rename from doc/ruby/long_optional.rb
rename to doc/optparse/ruby/long_optional.rb
diff --git a/doc/ruby/long_required.rb b/doc/optparse/ruby/long_required.rb
similarity index 100%
rename from doc/ruby/long_required.rb
rename to doc/optparse/ruby/long_required.rb
diff --git a/doc/ruby/long_simple.rb b/doc/optparse/ruby/long_simple.rb
similarity index 100%
rename from doc/ruby/long_simple.rb
rename to doc/optparse/ruby/long_simple.rb
diff --git a/doc/ruby/long_with_negation.rb b/doc/optparse/ruby/long_with_negation.rb
similarity index 100%
rename from doc/ruby/long_with_negation.rb
rename to doc/optparse/ruby/long_with_negation.rb
diff --git a/doc/ruby/matched_values.rb b/doc/optparse/ruby/matched_values.rb
similarity index 100%
rename from doc/ruby/matched_values.rb
rename to doc/optparse/ruby/matched_values.rb
diff --git a/doc/ruby/method.rb b/doc/optparse/ruby/method.rb
similarity index 100%
rename from doc/ruby/method.rb
rename to doc/optparse/ruby/method.rb
diff --git a/doc/ruby/missing_options.rb b/doc/optparse/ruby/missing_options.rb
similarity index 100%
rename from doc/ruby/missing_options.rb
rename to doc/optparse/ruby/missing_options.rb
diff --git a/doc/ruby/mixed_names.rb b/doc/optparse/ruby/mixed_names.rb
similarity index 100%
rename from doc/ruby/mixed_names.rb
rename to doc/optparse/ruby/mixed_names.rb
diff --git a/doc/ruby/no_abbreviation.rb b/doc/optparse/ruby/no_abbreviation.rb
similarity index 100%
rename from doc/ruby/no_abbreviation.rb
rename to doc/optparse/ruby/no_abbreviation.rb
diff --git a/doc/ruby/numeric.rb b/doc/optparse/ruby/numeric.rb
similarity index 100%
rename from doc/ruby/numeric.rb
rename to doc/optparse/ruby/numeric.rb
diff --git a/doc/ruby/object.rb b/doc/optparse/ruby/object.rb
similarity index 100%
rename from doc/ruby/object.rb
rename to doc/optparse/ruby/object.rb
diff --git a/doc/ruby/octal_integer.rb b/doc/optparse/ruby/octal_integer.rb
similarity index 100%
rename from doc/ruby/octal_integer.rb
rename to doc/optparse/ruby/octal_integer.rb
diff --git a/doc/ruby/optional_argument.rb b/doc/optparse/ruby/optional_argument.rb
similarity index 100%
rename from doc/ruby/optional_argument.rb
rename to doc/optparse/ruby/optional_argument.rb
diff --git a/doc/ruby/proc.rb b/doc/optparse/ruby/proc.rb
similarity index 100%
rename from doc/ruby/proc.rb
rename to doc/optparse/ruby/proc.rb
diff --git a/doc/ruby/regexp.rb b/doc/optparse/ruby/regexp.rb
similarity index 100%
rename from doc/ruby/regexp.rb
rename to doc/optparse/ruby/regexp.rb
diff --git a/doc/ruby/required_argument.rb b/doc/optparse/ruby/required_argument.rb
similarity index 100%
rename from doc/ruby/required_argument.rb
rename to doc/optparse/ruby/required_argument.rb
diff --git a/doc/ruby/shellwords.rb b/doc/optparse/ruby/shellwords.rb
similarity index 100%
rename from doc/ruby/shellwords.rb
rename to doc/optparse/ruby/shellwords.rb
diff --git a/doc/ruby/short_names.rb b/doc/optparse/ruby/short_names.rb
similarity index 100%
rename from doc/ruby/short_names.rb
rename to doc/optparse/ruby/short_names.rb
diff --git a/doc/ruby/short_optional.rb b/doc/optparse/ruby/short_optional.rb
similarity index 100%
rename from doc/ruby/short_optional.rb
rename to doc/optparse/ruby/short_optional.rb
diff --git a/doc/ruby/short_range.rb b/doc/optparse/ruby/short_range.rb
similarity index 100%
rename from doc/ruby/short_range.rb
rename to doc/optparse/ruby/short_range.rb
diff --git a/doc/ruby/short_required.rb b/doc/optparse/ruby/short_required.rb
similarity index 100%
rename from doc/ruby/short_required.rb
rename to doc/optparse/ruby/short_required.rb
diff --git a/doc/ruby/short_simple.rb b/doc/optparse/ruby/short_simple.rb
similarity index 100%
rename from doc/ruby/short_simple.rb
rename to doc/optparse/ruby/short_simple.rb
diff --git a/doc/ruby/string.rb b/doc/optparse/ruby/string.rb
similarity index 100%
rename from doc/ruby/string.rb
rename to doc/optparse/ruby/string.rb
diff --git a/doc/ruby/terminator.rb b/doc/optparse/ruby/terminator.rb
similarity index 100%
rename from doc/ruby/terminator.rb
rename to doc/optparse/ruby/terminator.rb
diff --git a/doc/ruby/time.rb b/doc/optparse/ruby/time.rb
similarity index 100%
rename from doc/ruby/time.rb
rename to doc/optparse/ruby/time.rb
diff --git a/doc/ruby/true_class.rb b/doc/optparse/ruby/true_class.rb
similarity index 100%
rename from doc/ruby/true_class.rb
rename to doc/optparse/ruby/true_class.rb
diff --git a/doc/ruby/uri.rb b/doc/optparse/ruby/uri.rb
similarity index 100%
rename from doc/ruby/uri.rb
rename to doc/optparse/ruby/uri.rb
diff --git a/doc/tutorial.rdoc b/doc/optparse/tutorial.rdoc
similarity index 100%
rename from doc/tutorial.rdoc
rename to doc/optparse/tutorial.rdoc
diff --git a/lib/optparse.rb b/lib/optparse.rb
index 0f92eba8cf..2eedef58bc 100644
--- a/lib/optparse.rb
+++ b/lib/optparse.rb
@@ -1314,7 +1314,7 @@ XXX
   # :call-seq:
   #   make_switch(params, block = nil)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   def make_switch(opts, block = nil)
     short, long, nolong, style, pattern, conv, not_pattern, not_conv, not_style = [], [], []
@@ -1452,7 +1452,7 @@ XXX
   # :call-seq:
   #   define(*params, &block)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   def define(*opts, &block)
     top.append(*(sw = make_switch(opts, block)))
@@ -1462,7 +1462,7 @@ XXX
   # :call-seq:
   #   on(*params, &block)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   def on(*opts, &block)
     define(*opts, &block)
@@ -1473,7 +1473,7 @@ XXX
   # :call-seq:
   #   define_head(*params, &block)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   def define_head(*opts, &block)
     top.prepend(*(sw = make_switch(opts, block)))
@@ -1483,7 +1483,7 @@ XXX
   # :call-seq:
   #   on_head(*params, &block)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   # The new option is added at the head of the summary.
   #
@@ -1496,7 +1496,7 @@ XXX
   # :call-seq:
   #   define_tail(*params, &block)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   def define_tail(*opts, &block)
     base.append(*(sw = make_switch(opts, block)))
@@ -1507,7 +1507,7 @@ XXX
   # :call-seq:
   #   on_tail(*params, &block)
   #
-  # :include: ../doc/creates_option.rdoc
+  # :include: ../doc/optparse/creates_option.rdoc
   #
   # The new option is added at the tail of the summary.
   #
diff --git a/lib/optparse/kwargs.rb b/lib/optparse/kwargs.rb
index d858faf7b8..ccf20c65e9 100644
--- a/lib/optparse/kwargs.rb
+++ b/lib/optparse/kwargs.rb
@@ -5,7 +5,7 @@ class OptionParser
   # :call-seq:
   #   define_by_keywords(options, method, **params)
   #
-  # :include: ../../doc/creates_option.rdoc
+  # :include: ../../doc/optparse/creates_option.rdoc
   #
   def define_by_keywords(options, meth, **opts)
     meth.parameters.each do |type, name|