diff --git a/libexec/pyenv-global b/libexec/pyenv-global
index e7f64156..70af07b2 100755
--- a/libexec/pyenv-global
+++ b/libexec/pyenv-global
@@ -8,19 +8,19 @@ if [ "$1" = "--complete" ]; then
   exec pyenv-versions --bare
 fi
 
-PYENV_VERSIONS=($@)
+PYENV_VERSION=($@)
 PYENV_VERSION_FILE="${PYENV_ROOT}/version"
 
-if [ -n "$PYENV_VERSIONS" ]; then
-  pyenv-version-file-write "$PYENV_VERSION_FILE" "${PYENV_VERSIONS[@]}"
+if [ -n "$PYENV_VERSION" ]; then
+  pyenv-version-file-write "$PYENV_VERSION_FILE" "${PYENV_VERSION[@]}"
 else
-  IFS=: PYENV_VERSIONS=($(
+  IFS=: PYENV_VERSION=($(
     pyenv-version-file-read "$PYENV_VERSION_FILE" ||
     pyenv-version-file-read "${PYENV_ROOT}/global" ||
     pyenv-version-file-read "${PYENV_ROOT}/default" ||
     echo system
   ))
-  for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-    echo "$PYENV_VERSION"
+  for version in "${PYENV_VERSION[@]}"; do
+    echo "$version"
   done
 fi
diff --git a/libexec/pyenv-help b/libexec/pyenv-help
index 442367fc..05629d94 100755
--- a/libexec/pyenv-help
+++ b/libexec/pyenv-help
@@ -44,7 +44,7 @@ global) echo "usage: pyenv global <version>
 
 Sets the global Python version. You can override the global version at
 any time by setting a directory-specific version with \`pyenv local'
-or by setting the PYENV_VERSIONS environment variable.
+or by setting the PYENV_VERSION environment variable.
 
 $(print_set_version)"
 ;;
@@ -58,14 +58,14 @@ When you run a Python command, pyenv will look for an '.pyenv-version'
 file in the current directory and each parent directory. If no such
 file is found in the tree, pyenv will use the global Python version
 specified with \`pyenv global', or the version specified in the
-PYENV_VERSIONS environment variable.
+PYENV_VERSION environment variable.
 
 $(print_set_version)"
 ;;
 shell) echo "usage: pyenv shell <version>
        pyenv shell --unset
 
-Sets a shell-specific Python version by setting the 'PYENV_VERSIONS'
+Sets a shell-specific Python version by setting the 'PYENV_VERSION'
 environment variable in your shell. This version overrides both
 project-specific versions and the global version.
 
diff --git a/libexec/pyenv-local b/libexec/pyenv-local
index 5b62a95f..8f41feab 100755
--- a/libexec/pyenv-local
+++ b/libexec/pyenv-local
@@ -9,21 +9,21 @@ if [ "$1" = "--complete" ]; then
   exec pyenv-versions --bare
 fi
 
-PYENV_VERSIONS=($@)
+PYENV_VERSION=($@)
 PYENV_VERSION_FILE=".pyenv-version"
 
-if [ "$PYENV_VERSIONS" = "--unset" ]; then
+if [ "$PYENV_VERSION" = "--unset" ]; then
   rm -f "$PYENV_VERSION_FILE"
-elif [ -n "$PYENV_VERSIONS" ]; then
-  pyenv-version-file-write "$PYENV_VERSION_FILE" "${PYENV_VERSIONS[@]}"
+elif [ -n "$PYENV_VERSION" ]; then
+  pyenv-version-file-write "$PYENV_VERSION_FILE" "${PYENV_VERSION[@]}"
 else
-  IFS=: PYENV_VERSIONS=($(
+  IFS=: PYENV_VERSION=($(
     pyenv-version-file-read "$PYENV_VERSION_FILE" ||
     { echo "pyenv: no local version configured for this directory"
       exit 1
     } >&2
   ))
-  for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-    echo "$PYENV_VERSION"
+  for version in "${PYENV_VERSION[@]}"; do
+    echo "$version"
   done
 fi
diff --git a/libexec/pyenv-prefix b/libexec/pyenv-prefix
index 38163a33..c1569f7b 100755
--- a/libexec/pyenv-prefix
+++ b/libexec/pyenv-prefix
@@ -9,24 +9,24 @@ if [ "$1" = "--complete" ]; then
 fi
 
 if [ -n "$1" ]; then
-  export PYENV_VERSIONS=($@)
+  export PYENV_VERSION=($@)
 else
-  IFS=: PYENV_VERSIONS=($(pyenv-version-name))
+  IFS=: PYENV_VERSION=($(pyenv-version-name))
 fi
 
-if [ "$PYENV_VERSIONS" = "system" ]; then
+if [ "$PYENV_VERSION" = "system" ]; then
   PYTHON_PATH="$(pyenv-which python)"
   echo "${PYTHON_PATH%/*}"
   exit
 fi
 
 PYENV_PREFIX_PATHS=()
-for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-  PYENV_PREFIX_PATH="${PYENV_ROOT}/versions/${PYENV_VERSION}"
+for version in "${PYENV_VERSION[@]}"; do
+  PYENV_PREFIX_PATH="${PYENV_ROOT}/versions/${version}"
   if [ -d "$PYENV_PREFIX_PATH" ]; then
     PYENV_PREFIX_PATHS=("${PYENV_PREFIX_PATHS[@]}" "$PYENV_PREFIX_PATH")
   else
-    echo "pyenv: version \`${PYENV_VERSION}' not installed" >&2
+    echo "pyenv: version \`${version}' not installed" >&2
     exit 1
   fi
 done
diff --git a/libexec/pyenv-sh-shell b/libexec/pyenv-sh-shell
index f54dceba..da7c3a7f 100755
--- a/libexec/pyenv-sh-shell
+++ b/libexec/pyenv-sh-shell
@@ -15,17 +15,17 @@ for version in "$@"; do
 done
 
 if [ -z "$versions" ]; then
-  if [ -z "$PYENV_VERSIONS" ]; then
+  if [ -z "$PYENV_VERSION" ]; then
     echo "pyenv: no shell-specific version configured" >&2
     exit 1
   else
-    echo "echo \"\$PYENV_VERSIONS\""
+    echo "echo \"\${PYENV_VERSION[@]}\""
     exit
   fi
 fi
 
 if [ "$versions" = "--unset" ]; then
-  echo "unset PYENV_VERSIONS"
+  echo "unset PYENV_VERSION"
   exit 1
 fi
 
@@ -34,5 +34,5 @@ pyenv-prefix $versions >/dev/null
 
 {
   IFS=:
-  echo "export PYENV_VERSIONS=\"${versions[*]}\""
+  echo "export PYENV_VERSION=(\"${versions[@]}\")"
 }
diff --git a/libexec/pyenv-version-file-write b/libexec/pyenv-version-file-write
index befe595c..9904c8ef 100755
--- a/libexec/pyenv-version-file-write
+++ b/libexec/pyenv-version-file-write
@@ -4,23 +4,23 @@ set -e
 
 PYENV_VERSION_FILE="$1"
 shift
-PYENV_VERSIONS=()
+PYENV_VERSION=()
 for version in "$@"; do
-  PYENV_VERSIONS=("${PYENV_VERSIONS[@]}" "$version")
+  PYENV_VERSION=("${PYENV_VERSION[@]}" "$version")
 done
 
-if [ -z "$PYENV_VERSIONS" ] || [ -z "$PYENV_VERSION_FILE" ]; then
+if [ -z "$PYENV_VERSION" ] || [ -z "$PYENV_VERSION_FILE" ]; then
   echo "usage: pyenv write-version-file FILENAME VERSIONS..." >&2
   exit 1
 fi
 
 # Make sure the specified version is installed.
-for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-  pyenv-prefix "$PYENV_VERSION" >/dev/null
+for version in "${PYENV_VERSION[@]}"; do
+  pyenv-prefix "$version" >/dev/null
 done
 
 # Write the version out to disk.
 rm -f "$PYENV_VERSION_FILE"
-for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-  echo "$PYENV_VERSION" >> "$PYENV_VERSION_FILE"
+for version in "${PYENV_VERSION[@]}"; do
+  echo "$version" >> "$PYENV_VERSION_FILE"
 done
diff --git a/libexec/pyenv-version-name b/libexec/pyenv-version-name
index fec0f16a..c09f7255 100755
--- a/libexec/pyenv-version-name
+++ b/libexec/pyenv-version-name
@@ -2,23 +2,23 @@
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
-if [ -z "$PYENV_VERSIONS" ]; then
+if [ -z "$PYENV_VERSION" ]; then
   PYENV_VERSION_FILE="$(pyenv-version-file)"
-  IFS=: PYENV_VERSIONS=($(pyenv-version-file-read "$PYENV_VERSION_FILE" || true))
+  IFS=: PYENV_VERSION=($(pyenv-version-file-read "$PYENV_VERSION_FILE" || true))
 fi
 
-if [ -z "$PYENV_VERSIONS" ] || [ "$PYENV_VERSIONS" = "system" ] ; then
+if [ -z "$PYENV_VERSION" ] || [ "$PYENV_VERSION" = "system" ] ; then
   echo "system"
   exit
 fi
 
-for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-  PYENV_VERSION_PATH="${PYENV_ROOT}/versions/${PYENV_VERSION}"
+for version in "${PYENV_VERSION[@]}"; do
+  PYENV_VERSION_PATH="${PYENV_ROOT}/versions/${version}"
   
   if [ ! -d "$PYENV_VERSION_PATH" ]; then
-    echo "pyenv: version \`$PYENV_VERSION' is not installed" >&2
+    echo "pyenv: version \`$version' is not installed" >&2
     exit 1
   fi
 done
 
-IFS=: echo "${PYENV_VERSIONS[*]}"
+IFS=: echo "${PYENV_VERSION[*]}"
diff --git a/libexec/pyenv-which b/libexec/pyenv-which
index 26b1675d..c9a95434 100755
--- a/libexec/pyenv-which
+++ b/libexec/pyenv-which
@@ -40,7 +40,7 @@ remove_from_path() {
   echo "${result%:}"
 }
 
-IFS=: PYENV_VERSIONS=($(pyenv-version-name))
+IFS=: PYENV_VERSION=($(pyenv-version-name))
 PYENV_COMMAND="$1"
 
 if [ -z "$PYENV_COMMAND" ]; then
@@ -48,12 +48,12 @@ if [ -z "$PYENV_COMMAND" ]; then
   exit 1
 fi
 
-for PYENV_VERSION in "${PYENV_VERSIONS[@]}"; do
-  if [ "$PYENV_VERSION" = "system" ]; then
+for version in "${PYENV_VERSION[@]}"; do
+  if [ "$version" = "system" ]; then
     PATH="$(remote_from_path "${PYENV_ROOT}/shims")"
     PYENV_COMMAND_PATH="$(command -v "$PYENV_COMMAND")"
   else
-    PYENV_COMMAND_PATH="${PYENV_ROOT}/versions/${PYENV_VERSION}/bin/${PYENV_COMMAND}"
+    PYENV_COMMAND_PATH="${PYENV_ROOT}/versions/${version}/bin/${PYENV_COMMAND}"
     if [ -x "$PYENV_COMMAND_PATH" ]; then
       break
     fi