diff --git a/bin/pyenv-sh-activate b/bin/pyenv-sh-activate
index 20d66a0..355c344 100755
--- a/bin/pyenv-sh-activate
+++ b/bin/pyenv-sh-activate
@@ -99,17 +99,20 @@ if [ -z "$no_shell" ]; then
   echo "pyenv shell \"${versions}\";"
 fi
 
+prefix="$(pyenv-prefix "${versions}")"
 case "$shell" in
 fish )
   cat <<EOS
 set -e PYENV_DEACTIVATE;
-. "$(pyenv-prefix "${versions}")/bin/activate.fish";
+setenv PYENV_ACTIVATE "${prefix}";
+. "${prefix}/bin/activate.fish";
 EOS
  ;;
 *    )
   cat <<EOS
 unset PYENV_DEACTIVATE;
-source "$(pyenv-prefix "${versions}")/bin/activate";
+export PYENV_ACTIVATE="${prefix}";
+source "${prefix}/bin/activate";
 EOS
   ;;
 esac
diff --git a/bin/pyenv-sh-deactivate b/bin/pyenv-sh-deactivate
index 8892305..7c1171d 100755
--- a/bin/pyenv-sh-deactivate
+++ b/bin/pyenv-sh-deactivate
@@ -38,7 +38,7 @@ fish )
 esac
 
 if [ -n "$VERBOSE" ]; then
-  echo "  echo \"pyenv-virtualenv: deactivate ${VIRTUAL_ENV##*/}\" 1>&2;"
+  echo "  echo \"pyenv-virtualenv: deactivate ${PYENV_ACTIVATE##*/}\" 1>&2;"
 fi
 
 if [ -z "${PYENV_VIRTUALENV_INIT}" ]; then
@@ -50,14 +50,16 @@ fi
 case "$shell" in
 fish )
   cat <<EOS
-  setenv PYENV_DEACTIVATE "$VIRTUAL_ENV";
+  setenv PYENV_DEACTIVATE "$PYENV_ACTIVATE";
+  set -e PYENV_ACTIVATE;
   deactivate;
 else;
 EOS
   ;;
 *    )
   cat <<EOS
-  export PYENV_DEACTIVATE="$VIRTUAL_ENV";
+  export PYENV_DEACTIVATE="$PYENV_ACTIVATE";
+  unset PYENV_ACTIVATE;
   deactivate;
 else
 EOS
diff --git a/bin/pyenv-virtualenv-init b/bin/pyenv-virtualenv-init
index 6643b4d..3eba180 100755
--- a/bin/pyenv-virtualenv-init
+++ b/bin/pyenv-virtualenv-init
@@ -75,12 +75,12 @@ case "$shell" in
 fish )
   cat <<EOS
 function _pyenv_virtualenv_hook --on-event fish_prompt;
-  if [ -n "\$VIRTUAL_ENV" ]
+  if [ -n "\$PYENV_ACTIVATE" ]
     if [ (pyenv version-name) = "system" ]
       eval (pyenv sh-deactivate --no-error --verbose)
       return 0
     end
-    if [ "\$VIRTUAL_ENV" != (pyenv prefix) ]
+    if [ "\$PYENV_ACTIVATE" != (pyenv prefix) ]
       eval (pyenv sh-deactivate --no-error --verbose)
       eval (pyenv sh-activate --no-error --verbose)
     end
@@ -106,12 +106,12 @@ esac
 
 if [[ "$shell" != "fish" ]]; then
   cat <<EOS
-  if [ -n "\$VIRTUAL_ENV" ]; then
+  if [ -n "\$PYENV_ACTIVATE" ]; then
     if [ "x\`pyenv version-name\`" = "xsystem" ]; then
       pyenv deactivate --no-error --verbose
       return 0
     fi
-    if [ "x\$VIRTUAL_ENV" != "x\`pyenv prefix\`" ]; then
+    if [ "x\$PYENV_ACTIVATE" != "x\`pyenv prefix\`" ]; then
       pyenv deactivate --no-error --verbose
       pyenv activate --no-error --verbose
     fi
diff --git a/test/activate.bats b/test/activate.bats
index 5b71407..565ff77 100644
--- a/test/activate.bats
+++ b/test/activate.bats
@@ -23,6 +23,7 @@ setup() {
   assert_success
   assert_output <<EOS
 unset PYENV_DEACTIVATE;
+export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv";
 source "${PYENV_ROOT}/versions/venv/bin/activate";
 EOS
 }
@@ -44,6 +45,7 @@ EOS
   assert_output <<EOS
 pyenv-virtualenv: activate venv
 unset PYENV_DEACTIVATE;
+export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv";
 source "${PYENV_ROOT}/versions/venv/bin/activate";
 EOS
 }
@@ -65,6 +67,7 @@ EOS
   assert_output <<EOS
 pyenv shell "venv";
 unset PYENV_DEACTIVATE;
+export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv";
 source "${PYENV_ROOT}/versions/venv/bin/activate";
 EOS
 }
@@ -85,6 +88,7 @@ EOS
   assert_success
   assert_output <<EOS
 set -e PYENV_DEACTIVATE;
+setenv PYENV_ACTIVATE "${PYENV_ROOT}/versions/venv";
 . "${PYENV_ROOT}/versions/venv/bin/activate.fish";
 EOS
 }
@@ -106,6 +110,7 @@ EOS
   assert_output <<EOS
 pyenv shell "venv";
 set -e PYENV_DEACTIVATE;
+setenv PYENV_ACTIVATE "${PYENV_ROOT}/versions/venv";
 . "${PYENV_ROOT}/versions/venv/bin/activate.fish";
 EOS
 }
@@ -125,6 +130,7 @@ EOS
   assert_output <<EOS
 pyenv shell "venv27";
 unset PYENV_DEACTIVATE;
+export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv27";
 source "${PYENV_ROOT}/versions/venv27/bin/activate";
 EOS
 }
@@ -144,6 +150,7 @@ EOS
   assert_output <<EOS
 pyenv shell "venv27";
 unset PYENV_DEACTIVATE;
+export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv27";
 source "${PYENV_ROOT}/versions/venv27/bin/activate";
 EOS
 }
diff --git a/test/deactivate.bats b/test/deactivate.bats
index ae058c8..b44c5ca 100644
--- a/test/deactivate.bats
+++ b/test/deactivate.bats
@@ -8,14 +8,15 @@ setup() {
 
 @test "deactivate virtualenv" {
   export PYENV_VIRTUALENV_INIT=1
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="bash" run pyenv-sh-deactivate
 
   assert_success
   assert_output <<EOS
 if declare -f deactivate 1>/dev/null 2>&1; then
-  export PYENV_DEACTIVATE="$VIRTUAL_ENV";
+  export PYENV_DEACTIVATE="$PYENV_ACTIVATE";
+  unset PYENV_ACTIVATE;
   deactivate;
 else
   echo "pyenv-virtualenv: no virtualenv has been activated." 1>&2;
@@ -26,7 +27,7 @@ EOS
 
 @test "deactivate virtualenv (verbose)" {
   export PYENV_VIRTUALENV_INIT=1
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="bash" run pyenv-sh-deactivate --verbose
 
@@ -34,7 +35,8 @@ EOS
   assert_output <<EOS
 if declare -f deactivate 1>/dev/null 2>&1; then
   echo "pyenv-virtualenv: deactivate venv" 1>&2;
-  export PYENV_DEACTIVATE="$VIRTUAL_ENV";
+  export PYENV_DEACTIVATE="$PYENV_ACTIVATE";
+  unset PYENV_ACTIVATE;
   deactivate;
 else
   echo "pyenv-virtualenv: no virtualenv has been activated." 1>&2;
@@ -45,14 +47,15 @@ EOS
 
 @test "deactivate virtualenv (no-error)" {
   export PYENV_VIRTUALENV_INIT=1
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="bash" run pyenv-sh-deactivate --no-error
 
   assert_success
   assert_output <<EOS
 if declare -f deactivate 1>/dev/null 2>&1; then
-  export PYENV_DEACTIVATE="$VIRTUAL_ENV";
+  export PYENV_DEACTIVATE="$PYENV_ACTIVATE";
+  unset PYENV_ACTIVATE;
   deactivate;
 else
   false;
@@ -62,7 +65,7 @@ EOS
 
 @test "deactivate virtualenv (without pyenv-virtualenv-init)" {
   export PYENV_VIRTUALENV_INIT=
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="bash" run pyenv-sh-deactivate
 
@@ -70,7 +73,8 @@ EOS
   assert_output <<EOS
 if declare -f deactivate 1>/dev/null 2>&1; then
   pyenv shell --unset;
-  export PYENV_DEACTIVATE="$VIRTUAL_ENV";
+  export PYENV_DEACTIVATE="$PYENV_ACTIVATE";
+  unset PYENV_ACTIVATE;
   deactivate;
 else
   echo "pyenv-virtualenv: no virtualenv has been activated." 1>&2;
@@ -81,7 +85,7 @@ EOS
 
 @test "deactivate virtualenv (without pyenv-virtualenv-init) (no-error)" {
   export PYENV_VIRTUALENV_INIT=
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="bash" run pyenv-sh-deactivate --no-error
 
@@ -89,7 +93,8 @@ EOS
   assert_output <<EOS
 if declare -f deactivate 1>/dev/null 2>&1; then
   pyenv shell --unset;
-  export PYENV_DEACTIVATE="$VIRTUAL_ENV";
+  export PYENV_DEACTIVATE="$PYENV_ACTIVATE";
+  unset PYENV_ACTIVATE;
   deactivate;
 else
   false;
@@ -99,14 +104,15 @@ EOS
 
 @test "deactivate virtualenv (fish)" {
   export PYENV_VIRTUALENV_INIT=1
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="fish" run pyenv-sh-deactivate
 
   assert_success
   assert_output <<EOS
 if functions -q deactivate
-  setenv PYENV_DEACTIVATE "$VIRTUAL_ENV";
+  setenv PYENV_DEACTIVATE "$PYENV_ACTIVATE";
+  set -e PYENV_ACTIVATE;
   deactivate;
 else;
   echo "pyenv-virtualenv: no virtualenv has been activated." 1>&2;
@@ -117,14 +123,15 @@ EOS
 
 @test "deactivate virtualenv (fish) (no-error)" {
   export PYENV_VIRTUALENV_INIT=1
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="fish" run pyenv-sh-deactivate --no-error
 
   assert_success
   assert_output <<EOS
 if functions -q deactivate
-  setenv PYENV_DEACTIVATE "$VIRTUAL_ENV";
+  setenv PYENV_DEACTIVATE "$PYENV_ACTIVATE";
+  set -e PYENV_ACTIVATE;
   deactivate;
 else;
   false;
@@ -134,7 +141,7 @@ EOS
 
 @test "deactivate virtualenv (fish) (without pyenv-virtualenv-init)" {
   export PYENV_VIRTUALENV_INIT=
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="fish" run pyenv-sh-deactivate
 
@@ -142,7 +149,8 @@ EOS
   assert_output <<EOS
 if functions -q deactivate
   pyenv shell --unset;
-  setenv PYENV_DEACTIVATE "$VIRTUAL_ENV";
+  setenv PYENV_DEACTIVATE "$PYENV_ACTIVATE";
+  set -e PYENV_ACTIVATE;
   deactivate;
 else;
   echo "pyenv-virtualenv: no virtualenv has been activated." 1>&2;
@@ -153,7 +161,7 @@ EOS
 
 @test "deactivate virtualenv (fish) (without pyenv-virtualenv-init) (no-error)" {
   export PYENV_VIRTUALENV_INIT=
-  export VIRTUAL_ENV="${PYENV_ROOT}/versions/venv"
+  export PYENV_ACTIVATE="${PYENV_ROOT}/versions/venv"
 
   PYENV_SHELL="fish" run pyenv-sh-deactivate --no-error
 
@@ -161,7 +169,8 @@ EOS
   assert_output <<EOS
 if functions -q deactivate
   pyenv shell --unset;
-  setenv PYENV_DEACTIVATE "$VIRTUAL_ENV";
+  setenv PYENV_DEACTIVATE "$PYENV_ACTIVATE";
+  set -e PYENV_ACTIVATE;
   deactivate;
 else;
   false;
diff --git a/test/init.bats b/test/init.bats
index 0e17801..7c29a5b 100644
--- a/test/init.bats
+++ b/test/init.bats
@@ -31,12 +31,12 @@ load test_helper
   assert_output <<EOS
 export PYENV_VIRTUALENV_INIT=1;
 _pyenv_virtualenv_hook() {
-  if [ -n "\$VIRTUAL_ENV" ]; then
+  if [ -n "\$PYENV_ACTIVATE" ]; then
     if [ "x\`pyenv version-name\`" = "xsystem" ]; then
       pyenv deactivate --no-error --verbose
       return 0
     fi
-    if [ "x\$VIRTUAL_ENV" != "x\`pyenv prefix\`" ]; then
+    if [ "x\$PYENV_ACTIVATE" != "x\`pyenv prefix\`" ]; then
       pyenv deactivate --no-error --verbose
       pyenv activate --no-error --verbose
     fi
@@ -58,12 +58,12 @@ EOS
   assert_output <<EOS
 setenv PYENV_VIRTUALENV_INIT 1;
 function _pyenv_virtualenv_hook --on-event fish_prompt;
-  if [ -n "\$VIRTUAL_ENV" ]
+  if [ -n "\$PYENV_ACTIVATE" ]
     if [ (pyenv version-name) = "system" ]
       eval (pyenv sh-deactivate --no-error --verbose)
       return 0
     end
-    if [ "\$VIRTUAL_ENV" != (pyenv prefix) ]
+    if [ "\$PYENV_ACTIVATE" != (pyenv prefix) ]
       eval (pyenv sh-deactivate --no-error --verbose)
       eval (pyenv sh-activate --no-error --verbose)
     end
@@ -82,12 +82,12 @@ EOS
   assert_output <<EOS
 export PYENV_VIRTUALENV_INIT=1;
 _pyenv_virtualenv_hook() {
-  if [ -n "\$VIRTUAL_ENV" ]; then
+  if [ -n "\$PYENV_ACTIVATE" ]; then
     if [ "x\`pyenv version-name\`" = "xsystem" ]; then
       pyenv deactivate --no-error --verbose
       return 0
     fi
-    if [ "x\$VIRTUAL_ENV" != "x\`pyenv prefix\`" ]; then
+    if [ "x\$PYENV_ACTIVATE" != "x\`pyenv prefix\`" ]; then
       pyenv deactivate --no-error --verbose
       pyenv activate --no-error --verbose
     fi