diff --git a/completion/available/gem.completion.bash b/completion/available/gem.completion.bash
index de986e08..1967d38d 100644
--- a/completion/available/gem.completion.bash
+++ b/completion/available/gem.completion.bash
@@ -1,36 +1,32 @@
 #!/usr/bin/env bash
 # Completion for gem
 
-_installcomp() {
-  if [ -z "$REMOTE_GEMS" ]
-  then
+__gem_installcomp() {
+  if [[ -z "$REMOTE_GEMS" ]] ; then
     REMOTE_GEMS=( $(gem list --remote --no-versions | tr '\n' ' ') )
   fi
-  
   local cur=${COMP_WORDS[COMP_CWORD]}
   COMPREPLY=( $(compgen -W "${REMOTE_GEMS[*]}" -- $cur) )
 }
 
-_uninstallcomp() {
-  if [ -z "$LOCAL_GEMS" ]
-  then
+__gem_uninstallcomp() {
+  if [[ -z "$LOCAL_GEMS" ]] ; then
     LOCAL_GEMS=( $(gem list --no-versions | sed 's/\*\*\* LOCAL GEMS \*\*\*//' | tr '\n' ' ') )
   fi
-  
   local cur=${COMP_WORDS[COMP_CWORD]}
   COMPREPLY=( $(compgen -W "${LOCAL_GEMS[*]}" -- $cur) )
 }
 
-_gem() {
+__gem_comp() {
   local cur=${COMP_WORDS[COMP_CWORD]}
   local prev=${COMP_WORDS[COMP_CWORD-1]}
   case $prev in
     install)
-      _installcomp
+      __gem_installcomp
       return 0
       ;;
     uninstall)
-      _uninstallcomp
+      __gem_uninstallcomp
       return 0
       ;;
   esac
@@ -38,4 +34,4 @@ _gem() {
   COMPREPLY=( $(compgen -W "${commands[*]}" -- $cur) )
 }
 
-complete -F _gem gem
+complete -F __gem_comp gem
diff --git a/completion/available/rbenv.completion.bash b/completion/available/rbenv.completion.bash
new file mode 100644
index 00000000..5a10cef8
--- /dev/null
+++ b/completion/available/rbenv.completion.bash
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+# Bash completion support for rbenv
+
+if _command_exists rbenv && [[ -r "$(dirname $(readlink -f $(which rbenv)))/../completions/rbenv.bash" ]] ; then
+  source "$(dirname $(readlink -f $(which rbenv)))/../completions/rbenv.bash"
+fi
diff --git a/plugins/available/rbenv.plugin.bash b/plugins/available/rbenv.plugin.bash
index 2b01669d..1ac85a7e 100644
--- a/plugins/available/rbenv.plugin.bash
+++ b/plugins/available/rbenv.plugin.bash
@@ -1,7 +1,25 @@
 cite about-plugin
 about-plugin 'load rbenv, if you are using it'
 
-export RBENV_ROOT="$HOME/.rbenv"
-pathmunge "$RBENV_ROOT/bin"
+# Load after basher
+# BASH_IT_LOAD_PRIORITY: 275
 
-[[ `which rbenv 2>/dev/null` ]] && eval "$(rbenv init - bash)"
+# Don't modify the environment if we can't find the tool:
+# - Check if in $PATH already
+# - Check if installed manually to $RBENV_ROOT
+# - Check if installed manually to $HOME
+_command_exists rbenv ||
+  [[ -n "$RBENV_ROOT" && -x "$RBENV_ROOT/bin/rbenv" ]] ||
+  [[ -x "$HOME/.rbenv/bin/rbenv" ]] ||
+  return 0
+
+# Set RBENV_ROOT, if not already set
+export RBENV_ROOT="${RBENV_ROOT:-$HOME/.rbenv}"
+
+# Add RBENV_ROOT/bin to PATH, if that's where it's installed
+if ! _command_exists rbenv && [[ -x "$RBENV_ROOT/bin/rbenv" ]] ; then
+  pathmunge "$RBENV_ROOT/bin"
+fi
+
+# Initialize rbenv
+eval "$(rbenv init - bash)"
diff --git a/plugins/available/ruby.plugin.bash b/plugins/available/ruby.plugin.bash
index 4ab891d9..e1c3fe85 100644
--- a/plugins/available/ruby.plugin.bash
+++ b/plugins/available/ruby.plugin.bash
@@ -1,16 +1,23 @@
 cite about-plugin
 about-plugin 'ruby and rubygems specific functions and settings'
 
-# Make commands installed with 'gem install --user-install' available
-# ~/.gem/ruby/${RUBY_VERSION}/bin/
-if which ruby >/dev/null && which gem >/dev/null; then
-  pathmunge "$(ruby -e 'print Gem.user_dir')/bin" after
-fi
+# Load after rbenv
+# BASH_IT_LOAD_PRIORITY: 285
+
+# Check ruby version to ensure rbenv can find ruby
+{ _command_exists ruby && ruby --version &>/dev/null ; } || return 0
+
+# Check gem version to ensure rbenv can find gem
+{ _command_exists gem && gem --version &>/dev/null ; } || return 0
 
 function remove_gem {
   about 'removes installed gem'
   param '1: installed gem name'
   group 'ruby'
 
-  gem list | grep $1 | awk '{ print $1; }' | xargs sudo gem uninstall
+  { _command_exists gem && gem --version &>/dev/null ; } || return 1
+  gem list | grep $1 | awk '{ print $1; }' | xargs gem uninstall
 }
+
+# Make commands installed with 'gem install --user-install' are available
+pathmunge "$(ruby -e 'print Gem.user_dir')/bin"
diff --git a/test/plugins/ruby.plugin.bats b/test/plugins/ruby.plugin.bats
index a45411e2..a820dbc0 100755
--- a/test/plugins/ruby.plugin.bats
+++ b/test/plugins/ruby.plugin.bats
@@ -3,13 +3,19 @@
 load ../test_helper
 load ../../lib/helpers
 load ../../lib/composure
-load ../../plugins/available/ruby.plugin
 
 function local_setup {
   setup_test_fixture
 
   export OLD_PATH="$PATH"
   export PATH="/usr/bin:/bin:/usr/sbin"
+
+  if ! _command_exists ruby || ! ruby --version &>/dev/null ; then
+    function ruby { echo -n "${HOME}/.gem/ruby/0.0.0" ; }
+  fi
+  if ! _command_exists gem || ! gem --version &>/dev/null ; then
+    function gem { return 0 ; }
+  fi
 }
 
 function local_teardown {
@@ -18,17 +24,15 @@ function local_teardown {
 }
 
 @test "plugins ruby: remove_gem is defined" {
+  load ../../plugins/available/ruby.plugin
   run type remove_gem
   assert_line -n 1 "remove_gem () "
 }
 
 @test "plugins ruby: PATH includes ~/.gem/ruby/bin" {
-  if ! which ruby >/dev/null; then
-    skip 'ruby not installed'
-  fi
-
   load ../../plugins/available/ruby.plugin
-
-  local last_path_entry=$(echo $PATH | tr ":" "\n" | tail -1)
-  [[ "${last_path_entry}" == "${HOME}"/.gem/ruby/*/bin ]]
+  local last_path_entry=$(echo $PATH | tr ":" "\n" | head -1)
+  # check that the path matches expectations, without getting caught up on the version number
+  assert_equal "${last_path_entry##/*/}" "bin"
+  assert_equal "${last_path_entry%/*/*}" "${HOME}/.gem/ruby"
 }