diff --git a/docs/man/man1/ansible.1.asciidoc b/docs/man/man1/ansible.1.asciidoc
index 27ca985b08..047c4adcf1 100644
--- a/docs/man/man1/ansible.1.asciidoc
+++ b/docs/man/man1/ansible.1.asciidoc
@@ -25,7 +25,7 @@ SSH.
 ARGUMENTS
 ---------
 
-*hostspec*
+*host-pattern*::
 
 A name of a group in the inventory file, a shell-like glob selecting hosts in inventory
 file, or any combination of the two seperated by semicolons.
@@ -75,6 +75,16 @@ FILES
 /usr/share/ansible -- Default module library
 
 
+ENVIRONMENT
+-----------
+
+The following environment variables may specified.
+
+ANSIBLE_HOSTS  -- Override the default ansible hosts file
+
+ANSIBLE_LIBRARY -- Override the default ansible module library path
+
+
 AUTHOR
 ------
 
@@ -95,7 +105,7 @@ SEE ALSO
 
 Ansible home page: <https://github.com/mpdehaan/ansible/>
 
-*ansible-modules*(5), 
+*ansible-modules*(5)
 
-*ansible-playbook*(5),
+*ansible-playbook*(5)
 
diff --git a/docs/man/man5/ansible-modules.5.asciidoc b/docs/man/man5/ansible-modules.5.asciidoc
index 760db571d0..afdd461b63 100644
--- a/docs/man/man5/ansible-modules.5.asciidoc
+++ b/docs/man/man5/ansible-modules.5.asciidoc
@@ -3,7 +3,7 @@ ansible-modules(5)
 :doctype:manpage
 :man source: Ansible-modules
 :man version: 0.0.1
-:man manual: System administration commands
+:man manual: Ansible
 
 
 NAME
@@ -23,7 +23,7 @@ IDEMPOTENCE
 
 Most modules other than command are idempotent, meaning they will seek to avoid changes
 unless a change needs to be made.  When using ansible playbooks, these modules can
-trigger change events, as described in ansible-playbooks (5).  
+trigger change events, as described in *ansible-playbooks*(5).
 
 Unless otherwise noted, all modules support change hooks.
 
@@ -148,7 +148,7 @@ setup
 
 Writes a JSON file containing key/value data, for use in templating.
 Call this once before using the template modules, usually as the very
-first step in your playbook. 
+first step in your playbook.
 
 If facter or ohai are installed, variables from these programs will also
 be snapshotted into the JSON file for usage in templating. These variables
@@ -212,6 +212,13 @@ To support change hooks, modules should return hashes, with a changed: True/Fals
 element at the top level.  Modules can also choose to indicate a failure scenario
 by returning a top level 'failure' element with a True value.
 
+
+ENVIRONMENT
+-----------
+
+ANSIBLE_LIBRARY -- Override the default ansible module library path
+
+
 AUTHOR
 ------
 
diff --git a/docs/man/man5/ansible-playbook.5.asciidoc b/docs/man/man5/ansible-playbook.5.asciidoc
index 5572629566..9bbcf9a9f7 100644
--- a/docs/man/man5/ansible-playbook.5.asciidoc
+++ b/docs/man/man5/ansible-playbook.5.asciidoc
@@ -3,7 +3,7 @@ ansible-modules(5)
 :doctype:manpage
 :man source: Ansible-playbook
 :man version: 0.0.1
-:man manual: System administration commands
+:man manual: Ansible
 
 
 NAME
@@ -28,13 +28,13 @@ Playbooks are written in YAML.
 EXAMPLE
 -------
 
-see 
+See:
 
-https://github.com/mpdehaan/ansible/blob/master/examples/playbook.yml
+- https://github.com/mpdehaan/ansible/blob/master/examples/playbook.yml
 
-https://github.com/mpdehaan/ansible/blob/master/examples/base.yml
+- https://github.com/mpdehaan/ansible/blob/master/examples/base.yml
 
-https://github.com/mpdehaan/ansible/blob/master/examples/handlers.yml
+- https://github.com/mpdehaan/ansible/blob/master/examples/handlers.yml
 
 WHAT THE EXAMPLE MEANS
 -----------------------
@@ -100,6 +100,12 @@ If a host has a failure, the host will be ignored for the remainder
 of the playbook execution.
 
 
+ENVIRONMENT
+-----------
+
+ANSIBLE_LIBRARY -- Override the default ansible module library path
+
+
 AUTHOR
 ------
 
diff --git a/hacking/env-setup b/hacking/env-setup
index 1f4af4e1a2..ca049f0775 100755
--- a/hacking/env-setup
+++ b/hacking/env-setup
@@ -2,10 +2,16 @@
 PREFIX_PYTHONPATH="`pwd`/lib/ansible:`pwd`/lib"
 PREFIX_PATH="`pwd`/bin"
 PREFIX_MANPATH="`pwd`/docs/man"
+PREFIX_ANS_LIBRARY="`pwd`/library"
 
 echo "Prefixing PYTHONPATH with $PREFIX_PYTHONPATH"
 export PYTHONPATH=$PREFIX_PYTHONPATH:$PYTHONPATH
+
 echo "Prefixing PATH with $PREFIX_PATH"
 export PATH=$PREFIX_PATH:$PATH
+
 echo "Prefixing MANPATH with $PREFIX_MANPATH"
 export MANPATH=$PREFIX_MANPATH:$MANPATH
+
+echo "Setting ANSIBLE_LIBRARY to ${PREFIX_ANS_LIBRARY}"
+export ANSIBLE_LIBRARY=${PREFIX_ANS_LIBRARY}
diff --git a/lib/ansible/constants.py b/lib/ansible/constants.py
index fde6a50363..3004d1a104 100644
--- a/lib/ansible/constants.py
+++ b/lib/ansible/constants.py
@@ -16,9 +16,14 @@
 # along with Ansible.  If not, see <http://www.gnu.org/licenses/>.
 #
 
+import os
+
+
 # control side (aka 'overlord')
-DEFAULT_HOST_LIST      = '/etc/ansible/hosts'
-DEFAULT_MODULE_PATH    = '/usr/share/ansible'
+DEFAULT_HOST_LIST      = os.environ.get('ANSIBLE_HOSTS',
+                                        '/etc/ansible/hosts')
+DEFAULT_MODULE_PATH    = os.environ.get('ANSIBLE_LIBRARY',
+                                        '/usr/share/ansible')
 DEFAULT_MODULE_NAME    = 'command'
 DEFAULT_PATTERN        = '*'
 DEFAULT_FORKS          = 5
@@ -26,4 +31,3 @@ DEFAULT_MODULE_ARGS    = ''
 DEFAULT_TIMEOUT        = 10
 DEFAULT_REMOTE_USER    = 'root'
 DEFAULT_REMOTE_PASS    = None
-