diff --git a/Makefile.am b/Makefile.am
index a38b135ebe..5190645791 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -278,3 +278,9 @@ dist-hook:
 include $(top_srcdir)/makefiles/testing.mak
 
 include $(top_srcdir)/makefiles/help.mak
+
+bashcompletiondir = @bashcompletiondir@
+if BASH_COMPLETION
+dist_bashcompletion_DATA  =
+dist_bashcompletion_DATA += completion/ctags.bash
+endif
diff --git a/completion/ctags.bash b/completion/ctags.bash
new file mode 100644
index 0000000000..090b0d9a00
--- /dev/null
+++ b/completion/ctags.bash
@@ -0,0 +1,649 @@
+#
+#  Copyright (c) 2022, Masatake YAMATO
+#  Copyright (c) 2022, Red Hat, Inc.
+#
+#  This source code is released for free distribution under the terms of the
+#  GNU General Public License version 2 or (at your option) any later version.
+#
+# TODO:
+# - Don't hard code column numbers when parsing --list-* output.
+# - Pass --options=NONE --quiet when running ctags internally; broken .ctags can cause a trouble.
+#
+
+_ctags_opts_arg_extras()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local lang
+    local L N l
+
+    local letters=()
+    local names=()
+
+    case "$prev" in
+	(--extras\=)
+	    :
+	    ;;
+	(--extras-*\=)
+	    local tmp=${prev#--extras-}
+	    lang=${tmp%=*}
+	    ;;
+	(*)
+	    return 1
+	    ;;
+    esac
+
+    while read L N l; do
+	if [[ -z "$lang" && "$l" == "NONE" ]] || [[ "$l" == "$lang" ]]; then
+	    if [[ "$L" != '-' ]]; then
+		letters+=($L)
+	    fi
+	    names+=('{'$N'}')
+	fi
+    done < <($ctags --with-list-header=no \
+		    --machinable=yes \
+		    --list-extras=$lang 2>/dev/null | cut -f1,2,4 -d$'\t')
+
+    target=${cur##*\{*\}}
+    if [[ "${target}" == "${target##*\{}" ]]; then
+	OPTS+=(\\\\* + -)
+	OPTS+=( "${letters[@]}" "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -W "${OPTS[*]}") )
+    else
+	target="${target##*\{}"
+	cur="${cur%\{*}"
+	OPTS+=( "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -P "$cur" -W "${OPTS[*]}" -- "{""$target" ) )
+    fi
+    return 0
+}
+
+_ctags_opts_arg_fields()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local lang
+    local L N l
+
+    local letters=()
+    local names=()
+
+    case "$prev" in
+	(--fields\=)
+	    :
+	    ;;
+	(--fields-*\=)
+	    local tmp=${prev#--fields-}
+	    lang=${tmp%=*}
+	    ;;
+	(*)
+	    return 1
+	    ;;
+    esac
+
+    while read L N l; do
+	if [[ -z "$lang" && "$l" == "NONE" ]] || [[ "$l" == "$lang" ]]; then
+	    if [[ "$L" != '-' ]]; then
+		letters+=($L)
+	    fi
+	    if [[ "$N" != 'NONE' ]]; then
+		names+=('{'$N'}')
+	    fi
+	fi
+    done < <($ctags --with-list-header=no \
+		    --machinable=yes \
+		    --list-fields=$lang 2>/dev/null | cut -f1,2,4 -d$'\t')
+
+    target=${cur##*\{*\}}
+    if [[ "${target}" == "${target##*\{}" ]]; then
+	OPTS+=(\\\\* + -)
+	OPTS+=( "${letters[@]}" "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -W "${OPTS[*]}") )
+    else
+	target="${target##*\{}"
+	cur="${cur%\{*}"
+	OPTS+=( "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -P "$cur" -W "${OPTS[*]}" -- "{""$target" ) )
+    fi
+    return 0
+}
+
+_ctags_opts_arg_kinds()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local lang
+    local L N
+
+    local letters=()
+    local names=()
+
+    local target=
+    local OPTS=()
+
+    case "$prev" in
+	--kinds-*\=)
+	    :
+	    ;;
+	*)
+	    return 1
+	    ;;
+    esac
+
+    local tmp=${prev#--kinds-}
+    lang=${tmp%=*}
+
+    while read L N; do
+	letters+=($L)
+	names+=('{'$N'}')
+    done  < <($ctags --with-list-header=no \
+		     --machinable=yes \
+		     --list-kinds-full=$lang 2>/dev/null | cut -f1,2 -d$'\t')
+
+    target=${cur##*\{*\}}
+    if [[ "${target}" == "${target##*\{}" ]]; then
+	OPTS+=(\\\\* + -)
+	OPTS+=( "${letters[@]}" "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -W "${OPTS[*]}") )
+    else
+	target="${target##*\{}"
+	cur="${cur%\{*}"
+	OPTS+=( "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -P "$cur" -W "${OPTS[*]}" -- "{""$target" ) )
+    fi
+    return 0
+}
+
+_ctags_opts_arg_ptags()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local N
+
+    local names=()
+
+    case "$prev" in
+	(--pseudo-tags\=)
+	    :
+	    ;;
+	(*)
+	    return 1
+	    ;;
+    esac
+
+    while read N; do
+	names+=('{'$N'}')
+    done < <($ctags --with-list-header=no \
+		    --machinable=yes \
+		    --list-pseudo-tags 2>/dev/null | cut -f1 -d$'\t')
+
+    target=${cur##*\{*\}}
+    if [[ "${target}" == "${target##*\{}" ]]; then
+	OPTS+=(\\\\* + -)
+	OPTS+=( "${letters[@]}" "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -W "${OPTS[*]}") )
+    else
+	target="${target##*\{}"
+	cur="${cur%\{*}"
+	OPTS+=( "${names[@]}" )
+	compopt -o nospace
+	COMPREPLY=( $(compgen -P "$cur" -W "${OPTS[*]}" -- "{""$target" ) )
+    fi
+    return 0
+}
+
+_ctags_opts_arg_yes_or_no()
+{
+    local prev=$1
+    local cur=$2
+
+    case $prev in
+	(--filter\=|\
+	    --links\=|\
+	    --recurse\=|\
+	    --append\=|\
+	    --use-slash-as-filename-separator\=|\
+	    --if0\=|\
+	    --line-directives\=|\
+	    --machinable\=|\
+	    --with-list-header\=|\
+	    --quiet=|\
+	    --verbose\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "yes no" -- "$cur") )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_arg_language_or_all()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local OPTS
+
+    ## TODO+
+    ## * --list-roles just completing language name is not enough; kind must be completed.
+    ## * --list-subparsers; limits languages having subparsers.
+    case $prev in
+	(--language-force\=|\
+	    --list-aliases\=|\
+	    --list-extras\=|\
+	    --list-fields\=|\
+	    --list-kinds\=|\
+	    --list-kinds-full\=|\
+	    --list-map-extensions\=|\
+	    --list-map-patterns\=|\
+	    --list-maps\=|\
+	    --list-params\=|\
+	    --list-roles\=|\
+	    --list-subparsers\=)
+	    OPTS=(
+		all
+		$($ctags --list-languages | grep -v '\[disabled\]')
+	    )
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "${OPTS[*]}" -- "$cur") )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_arg_language-list_or_all()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local OPTS=( all )
+
+    case $prev in
+	(--languages\=)
+	;;
+	(*)
+	    return 1
+	    ;;
+    esac
+
+    if [[ -z "${cur}" ]]; then
+	OPTS+=(+ -)
+    fi
+
+    local target prefix
+    local c=${cur:0:1}
+    local cur0
+    case "$c" in
+	(+|-)
+	    cur0=${cur:1}
+	    ;;
+	(*)
+	    c=
+	    cur0=$cur
+    esac
+
+    local target=${cur0##*,}
+    local prefix=$c${cur0%${target}}
+
+    while read L; do
+	OPTS+=(${L})
+	if [[ "$L" == "$target" ]]; then
+	    included="${L},"
+	fi
+    done < <($ctags --list-languages |
+		 grep -v '\[disabled\]')
+
+    OPTS+=($included)
+
+    COMPREPLY=( $(compgen -P "$prefix" -W "${OPTS[*]}" -- "$target") )
+    compopt -o nospace
+    compopt -o nosort
+    return 0
+}
+
+_ctags_opts_arg_file()
+{
+    local prev=$1
+
+    case $prev in
+	(--etags-include\=|\
+	    --options\=|\
+	    --options-maybe\=)
+	    local IFS=$'\n'
+	    compopt -o filenames
+	    COMPREPLY=( $(compgen -f -- ${cur:-"/"}) )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_arg_dir()
+{
+    local prev=$1
+
+    case $prev in
+	(--optib-dir\=)
+	    local IFS=$'\n'
+	    compopt -o dirnames
+	    COMPREPLY=( $(compgen -d -- ${cur:-"/"}) )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_arg()
+{
+    local ctags=$1
+    local prev=$2
+    local cur=$3
+
+    local OPTS
+
+    _ctags_opts_arg_yes_or_no "$prev" "$cur" && return 0
+    _ctags_opts_arg_language-list_or_all "$ctags" "$prev" "$cur" && return 0
+    _ctags_opts_arg_language_or_all "$ctags" "$prev" "$cur" && return 0
+    _ctags_opts_arg_fields "$ctags" "$prev" "$cur" && return 0
+    _ctags_opts_arg_extras "$ctags" "$prev" "$cur" && return 0
+    _ctags_opts_arg_kinds "$ctags" "$prev" "$cur" && return 0
+    _ctags_opts_arg_ptags "$ctags" "$prev" "$cur" && return 0
+    _ctags_opts_arg_file "$prev" && return 0
+    _ctags_opts_arg_dir "$prev" && return 0
+
+    case $prev in
+	(--format\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "1 2" -- "$cur") )
+	    return 0
+	    ;;
+	(--output-format\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "u-ctags e-ctags etags xref json" -- "$cur") )
+	    return 0
+	    ;;
+	(--sort\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "yes no foldcase" -- "$cur") )
+	    return 0
+	    ;;
+	(--excmd\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "number pattern mix combine" -- "$cur") )
+	    return 0
+	    ;;
+	(--tag-relative\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "yes no always never" -- "$cur") )
+	    return 0
+	    ;;
+	(--totals\=)
+	    compopt -o nosort
+	    COMPREPLY=( $(compgen -W "yes no extra" -- "$cur") )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_eq()
+{
+    local cur=$1
+
+    case $cur in
+	(--filter |\
+	    --links |\
+	    --recurse |\
+	    --append |\
+	    --use-slash-as-filename-separator |\
+	    --if0 |\
+	    --line-directives |\
+	    --list-aliases |\
+	    --list-extras |\
+	    --list-fields |\
+	    --list-kinds |\
+	    --list-kinds-full |\
+	    --list-map-extensions |\
+	    --list-map-patterns |\
+	    --list-maps |\
+	    --list-params |\
+	    --list-roles |\
+	    --list-subparsers |\
+	    --machinable |\
+	    --with-list-header |\
+	    --quiet |\
+	    --totals |\
+	    --verbose)
+	    compopt -o nospace
+	    COMPREPLY=( $(compgen -P $cur -W "=") )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_list()
+{
+    local OPTS=(
+	--list-aliases
+	--list-excludes
+	--list-extras
+	--list-features
+	--list-fields
+	--list-kinds
+	--list-kinds-full
+	--list-languages
+	--list-map-extensions
+	--list-map-patterns
+	--list-maps
+	--list-mline-regex-flags
+	--list-params
+	--list-pseudo-tags
+	--list-regex-flags
+	--list-roles
+	--list-subparsers)
+
+    case $cur in
+	(--list-*)
+	    COMPREPLY=( $(compgen -W "${OPTS[*]}" -- "$cur") )
+	    compopt -o nospace
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_file()
+{
+    local prev=$1
+    local cur=$2
+
+    case $prev in
+	(-L|-f|-o)
+	    local IFS=$'\n'
+	    compopt -o filenames
+	    COMPREPLY=('-'  $(compgen -f -- ${cur:-"/"}) )
+	    return 0
+	    ;;
+    esac
+    return 1
+}
+
+_ctags_opts_lang_eq()
+{
+    local ctags=$1
+    local cur=$2
+    local L P
+    local OPTS=()
+
+    case "$cur" in
+	(--input-endocing-*)
+	    P=--input-encoding-
+	    cur=${cur#--input-encoding-}
+	    ;;
+	(--alias-*)
+	    P=--alias-
+	    cur=${cur#--alias-}
+	    ;;
+	(--map-*)
+	    P=--map-
+	    cur=${cur#--map-}
+	    ;;
+	(--extras-*)
+	    P=--extras-
+	    cur=${cur#--extras-}
+	    ;;
+	(--fields-*)
+	    P=--fields-
+	    cur=${cur#--fields-}
+	    ;;
+	(--kinds-*)
+	    P=--kinds-
+	    cur=${cur#--kinds-}
+	    ;;
+	(--param-*)
+	    P=--param-
+	    cur=${cur#--param-}
+	    ;;
+	(*)
+	    return 1
+	    ;;
+    esac
+
+    while read L; do
+	OPTS+=(${L}=)
+    done < <($ctags --list-languages |
+		 grep -v '\[disabled\]')
+    COMPREPLY=( $(compgen -P $P -W "${OPTS[*]}" -- "$cur") )
+    [[ ${COMPREPLY-} == *= ||  ${COMPREPLY-} == *- ]] && compopt -o nospace
+    return 0
+}
+
+_ctags()
+{
+    local ctags="${COMP_WORDS[0]}"
+    local pprev cur OPTS pprev
+    COMPREPLY=()
+
+    cur="${COMP_WORDS[COMP_CWORD]}"
+    prev="${COMP_WORDS[COMP_CWORD-1]}"
+    pprev="${COMP_WORDS[COMP_CWORD-2]}"
+
+    _ctags_opts_arg "$ctags" "$pprev$prev" "$cur" && return 0
+    _ctags_opts_eq "$cur" && return 0
+    _ctags_opts_list "$cur" && return 0
+    _ctags_opts_lang_eq "$ctags" "$cur" && return 0
+    _ctags_file "$prev" "$cur" && return 0
+
+    case $cur in
+	(-*)
+	    OPTS=(
+		# Input/Output File Options
+		--exclude=
+		--exclude-exception=
+		--filter
+		--filter-terminator=
+		--links
+		--maxdepth=
+		--recurse -R
+		-L
+		--append -a
+		-f -o
+		--format=
+		# Output Format Options
+		--output-format= -e -x
+		--sort= -u
+		--etags-include=
+		## TODO encoding {{
+		--input-encoding=
+		--input-encoding-
+		--output-encoding=
+		## }}
+		# Language Selection and Mapping Options
+		--language-force=
+		--languages=
+		--alias-
+		--guess-language-eagerly -G
+		## TODO {{
+		--langmap=
+		## }}
+		--map-
+		# Tags File Contents Options
+		--excmd=
+		-n -N
+		--extras=
+		--extras-
+		--fields=
+		--fields-
+		--kinds-
+		--pattern-length-limit=
+		--pseudo-tags=
+		--put-field-prefix
+		## TODO+ language+kind {{
+		--roles-
+		## }}
+		--tag-relative=
+		--use-slash-as-filename-separator
+		-B -F
+		# Option File Options
+		--options=
+		--options-maybe=
+		--optib-dir=
+		# optlib Options
+		# Language Specific Options
+		--if0
+		--line-directives
+		-D
+		-h
+		-I
+		## TODO+ language.param {{
+		--param-
+		## }}
+		# Listing Options
+		--list-
+		--machinable
+		--with-list-header
+		# Miscellaneous Options
+		--help '-?'
+		--help-full
+		--license
+		--print-language
+		--quiet
+		--totals
+		--verbose -V
+		--version
+	    )
+	    COMPREPLY=( $(compgen -W "${OPTS[*]}" -- $cur) )
+	    [[ ${COMPREPLY-} == *= ||  ${COMPREPLY-} == *- ]] && compopt -o nospace
+	    return 0
+	    ;;
+	(\=)
+	    cur=${cur:1}
+	    _ctags_opts_arg "$ctags" "$prev"= "$cur" && return 0
+	    ;;
+    esac
+
+    local IFS=$'\n'
+    compopt -o filenames
+    COMPREPLY=( $(compgen -f -- ${cur:-"/"}) )
+    return 0
+}
+complete -F _ctags ctags
diff --git a/configure.ac b/configure.ac
index 5cea58b865..e9ee275361 100644
--- a/configure.ac
+++ b/configure.ac
@@ -841,6 +841,25 @@ if test "$ETAGS_NAME_EXECUTABLE" != etags ; then
 	AC_MSG_NOTICE(Changing name of 'etags' for $ETAGS_NAME_EXECUTABLE)
 fi
 
+AC_ARG_ENABLE([bash-completion],
+  AS_HELP_STRING([--disable-bash-completion], [do not install bash completion files]),
+  [], [enable_bash_completion=yes]
+)
+AM_CONDITIONAL([BASH_COMPLETION], [test "x$enable_bash_completion" = xyes])
+
+AC_ARG_WITH([bashcompletiondir],
+  AS_HELP_STRING([--with-bashcompletiondir=DIR], [Bash completions directory]),
+  [], [
+  AS_IF([test "x$enable_bash_completion" = xyes], [
+    PKG_CHECK_VAR([with_bashcompletiondir], [bash-completion], [completionsdir],
+      [],
+      [with_bashcompletiondir=${datadir}/bash-completion/completions])
+  ])
+])
+AS_IF([test "x$enable_bash_completion" = xyes], [
+  AC_SUBST([bashcompletiondir], [$with_bashcompletiondir])
+])
+
 # Output files
 # ------------