diff --git a/libexec/pyenv---version b/libexec/pyenv---version
index 874a3cc8..7a1df8a1 100755
--- a/libexec/pyenv---version
+++ b/libexec/pyenv---version
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Display the version of pyenv
 #
 # Displays the version number of this pyenv release, including the
diff --git a/libexec/pyenv-commands b/libexec/pyenv-commands
index 147d3d8a..283ce44b 100755
--- a/libexec/pyenv-commands
+++ b/libexec/pyenv-commands
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: List all available pyenv commands
 # Usage: pyenv commands [--sh|--no-sh]
 
diff --git a/libexec/pyenv-completions b/libexec/pyenv-completions
index 8ebf26b1..227b932e 100755
--- a/libexec/pyenv-completions
+++ b/libexec/pyenv-completions
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Usage: pyenv completions <command> [arg1 arg2...]
 
 set -e
diff --git a/libexec/pyenv-exec b/libexec/pyenv-exec
index 18829ad0..51c668e3 100755
--- a/libexec/pyenv-exec
+++ b/libexec/pyenv-exec
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Run an executable with the selected Python version
 #
 # Usage: pyenv exec <command> [arg1 arg2...]
diff --git a/libexec/pyenv-global b/libexec/pyenv-global
index 0905b446..102e082a 100755
--- a/libexec/pyenv-global
+++ b/libexec/pyenv-global
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Set or show the global Python version
 #
 # Usage: pyenv global <version>
diff --git a/libexec/pyenv-help b/libexec/pyenv-help
index 7fd4320b..8270993e 100755
--- a/libexec/pyenv-help
+++ b/libexec/pyenv-help
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Display help for a command
 #
 # Usage: pyenv help [--usage] COMMAND
diff --git a/libexec/pyenv-hooks b/libexec/pyenv-hooks
index 7a465b76..2c1620f3 100755
--- a/libexec/pyenv-hooks
+++ b/libexec/pyenv-hooks
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: List hook scripts for a given pyenv command
 # Usage: pyenv hooks <command>
 
diff --git a/libexec/pyenv-init b/libexec/pyenv-init
index 5ec7b234..659d1f4c 100755
--- a/libexec/pyenv-init
+++ b/libexec/pyenv-init
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Configure the shell environment for pyenv
 # Usage: eval "$(pyenv init - [--no-rehash] [<shell>])"
 
diff --git a/libexec/pyenv-local b/libexec/pyenv-local
index c1812a64..8a2a6747 100755
--- a/libexec/pyenv-local
+++ b/libexec/pyenv-local
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Set or show the local application-specific Python version
 #
 # Usage: pyenv local <version>
diff --git a/libexec/pyenv-prefix b/libexec/pyenv-prefix
index a836acca..ac04f6bc 100755
--- a/libexec/pyenv-prefix
+++ b/libexec/pyenv-prefix
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Display prefix for a Python version
 # Usage: pyenv prefix [<version>]
 #
diff --git a/libexec/pyenv-rehash b/libexec/pyenv-rehash
index 6e44e932..5c421c41 100755
--- a/libexec/pyenv-rehash
+++ b/libexec/pyenv-rehash
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Rehash pyenv shims (run this after installing executables)
 
 set -e
@@ -61,6 +62,7 @@ fi
 # serves as a locking mechanism.
 create_prototype_shim() {
   cat > "$PROTOTYPE_SHIM_PATH" <<SH
+#!/usr/bin/env bash
 set -e
 [ -n "\$PYENV_DEBUG" ] && set -x
 
diff --git a/libexec/pyenv-root b/libexec/pyenv-root
index 7614caae..b4a135f3 100755
--- a/libexec/pyenv-root
+++ b/libexec/pyenv-root
@@ -1,2 +1,3 @@
+#!/usr/bin/env bash
 # Summary: Display the root directory where versions and shims are kept
 echo "$PYENV_ROOT"
diff --git a/libexec/pyenv-sh-rehash b/libexec/pyenv-sh-rehash
index fe35b7dd..ab50346d 100755
--- a/libexec/pyenv-sh-rehash
+++ b/libexec/pyenv-sh-rehash
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
diff --git a/libexec/pyenv-sh-shell b/libexec/pyenv-sh-shell
index 7889e3ca..b38abbf3 100755
--- a/libexec/pyenv-sh-shell
+++ b/libexec/pyenv-sh-shell
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Set or show the shell-specific Python version
 #
 # Usage: pyenv shell <version>...
diff --git a/libexec/pyenv-shims b/libexec/pyenv-shims
index 35b9670b..43c6308a 100755
--- a/libexec/pyenv-shims
+++ b/libexec/pyenv-shims
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: List existing pyenv shims
 # Usage: pyenv shims [--short]
 
diff --git a/libexec/pyenv-version b/libexec/pyenv-version
index b4260f4d..dd5fa29a 100755
--- a/libexec/pyenv-version
+++ b/libexec/pyenv-version
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Show the current Python version and its origin
 #
 # Shows the currently selected Python version and how it was
diff --git a/libexec/pyenv-version-file b/libexec/pyenv-version-file
index aa855af7..91d8b0d3 100755
--- a/libexec/pyenv-version-file
+++ b/libexec/pyenv-version-file
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Usage: pyenv version-file [<dir>]
 # Summary: Detect the file that sets the current pyenv version
 set -e
diff --git a/libexec/pyenv-version-file-read b/libexec/pyenv-version-file-read
index f48f5efb..7d27d5a5 100755
--- a/libexec/pyenv-version-file-read
+++ b/libexec/pyenv-version-file-read
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Usage: pyenv version-file-read <file>
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
diff --git a/libexec/pyenv-version-file-write b/libexec/pyenv-version-file-write
index 7b635cff..7095140f 100755
--- a/libexec/pyenv-version-file-write
+++ b/libexec/pyenv-version-file-write
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Usage: pyenv version-file-write <file> <version>
 
 set -e
diff --git a/libexec/pyenv-version-name b/libexec/pyenv-version-name
index 0af63a26..65a198a4 100755
--- a/libexec/pyenv-version-name
+++ b/libexec/pyenv-version-name
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Show the current Python version
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
diff --git a/libexec/pyenv-version-origin b/libexec/pyenv-version-origin
index c5b0905b..1067a013 100755
--- a/libexec/pyenv-version-origin
+++ b/libexec/pyenv-version-origin
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: Explain how the current Python version is set
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
diff --git a/libexec/pyenv-versions b/libexec/pyenv-versions
index 9462b124..019c0e90 100755
--- a/libexec/pyenv-versions
+++ b/libexec/pyenv-versions
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: List all Python versions available to pyenv
 # Usage: pyenv versions [--bare] [--skip-aliases]
 #
diff --git a/libexec/pyenv-whence b/libexec/pyenv-whence
index 8ca1b2e8..fddcf112 100755
--- a/libexec/pyenv-whence
+++ b/libexec/pyenv-whence
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Summary: List all Python versions that contain the given executable
 # Usage: pyenv whence [--path] <command>
 
diff --git a/libexec/pyenv-which b/libexec/pyenv-which
index 02171332..9551f6cf 100755
--- a/libexec/pyenv-which
+++ b/libexec/pyenv-which
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Display the full path to an executable
 #
 # Usage: pyenv which <command>
diff --git a/plugins/python-build/bin/pyenv-install b/plugins/python-build/bin/pyenv-install
index 01d6cd2f..22333f6e 100755
--- a/plugins/python-build/bin/pyenv-install
+++ b/plugins/python-build/bin/pyenv-install
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Install a Python version using python-build
 #
 # Usage: pyenv install [-f] [-kvp] <version>
diff --git a/plugins/python-build/bin/pyenv-uninstall b/plugins/python-build/bin/pyenv-uninstall
index 662da776..91805454 100755
--- a/plugins/python-build/bin/pyenv-uninstall
+++ b/plugins/python-build/bin/pyenv-uninstall
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+#
 # Summary: Uninstall a specific Python version
 #
 # Usage: pyenv uninstall [-f|--force] <version>
diff --git a/plugins/python-build/test/stubs/stub b/plugins/python-build/test/stubs/stub
index 7494ef73..bd5c5d68 100755
--- a/plugins/python-build/test/stubs/stub
+++ b/plugins/python-build/test/stubs/stub
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 set -e
 
 status=0
diff --git a/pyenv.d/exec/pip-rehash/conda b/pyenv.d/exec/pip-rehash/conda
index 4398198a..ee5aefe8 100755
--- a/pyenv.d/exec/pip-rehash/conda
+++ b/pyenv.d/exec/pip-rehash/conda
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
diff --git a/pyenv.d/exec/pip-rehash/easy_install b/pyenv.d/exec/pip-rehash/easy_install
index de0dcfc3..cf559dcb 100755
--- a/pyenv.d/exec/pip-rehash/easy_install
+++ b/pyenv.d/exec/pip-rehash/easy_install
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
diff --git a/pyenv.d/exec/pip-rehash/pip b/pyenv.d/exec/pip-rehash/pip
index 542a6436..1d305937 100755
--- a/pyenv.d/exec/pip-rehash/pip
+++ b/pyenv.d/exec/pip-rehash/pip
@@ -1,3 +1,5 @@
+#!/usr/bin/env bash
+
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
diff --git a/test/init.bats b/test/init.bats
index 004f47d7..ead63d82 100755
--- a/test/init.bats
+++ b/test/init.bats
@@ -35,7 +35,7 @@ load test_helper
   cd "$PYENV_TEST_DIR"
   cat > myscript.sh <<OUT
 #!/bin/sh
-eval "\$(pyenv init -)"
+eval "\$(pyenv-init -)"
 echo \$PYENV_SHELL
 OUT
   chmod +x myscript.sh
diff --git a/test/libexec/pyenv-echo b/test/libexec/pyenv-echo
index 63b86bbb..ee322104 100755
--- a/test/libexec/pyenv-echo
+++ b/test/libexec/pyenv-echo
@@ -1,3 +1,4 @@
+#!/usr/bin/env bash
 # Usage: pyenv echo [-F<char>] VAR
 
 if [[ $1 == -F* ]]; then