diff --git a/config/default.yml b/config/default.yml
index 9c808f68..1e502d40 100644
--- a/config/default.yml
+++ b/config/default.yml
@@ -430,6 +430,12 @@ PostCheckout:
     description: 'Generating tags file from source'
     required_executable: 'ctags'
 
+  SubmoduleStatus:
+    enabled: false
+    description: 'Checking submodule status'
+    quiet: true
+    recursive: false
+
 # Hooks that run after a commit is created.
 PostCommit:
   ALL:
@@ -450,6 +456,12 @@ PostCommit:
     description: 'Generating tags file from source'
     required_executable: 'ctags'
 
+  SubmoduleStatus:
+    enabled: false
+    description: 'Checking submodule status'
+    quiet: true
+    recursive: false
+
 # Hooks that run after `git merge` executes successfully (no merge conflicts).
 PostMerge:
   ALL:
@@ -461,6 +473,12 @@ PostMerge:
     description: 'Generating tags file from source'
     required_executable: 'ctags'
 
+  SubmoduleStatus:
+    enabled: false
+    description: 'Checking submodule status'
+    quiet: true
+    recursive: false
+
 # Hooks that run after a commit is modified by an amend or rebase.
 PostRewrite:
   ALL:
@@ -472,6 +490,12 @@ PostRewrite:
     description: 'Generating tags file from source'
     required_executable: 'ctags'
 
+  SubmoduleStatus:
+    enabled: false
+    description: 'Checking submodule status'
+    quiet: true
+    recursive: false
+
 # Hooks that run during `git push`, after remote refs have been updated but
 # before any objects have been transferred.
 PrePush:
diff --git a/lib/overcommit/git_repo.rb b/lib/overcommit/git_repo.rb
index eb2e7e95..524cd7cc 100644
--- a/lib/overcommit/git_repo.rb
+++ b/lib/overcommit/git_repo.rb
@@ -11,6 +11,50 @@ module GitRepo
       \s@@.*$
     /x
 
+    # Regular expression used to extract information from lines of
+    # `git submodule status` output
+    SUBMODULE_STATUS_REGEX = /
+      ^\s*(?<prefix>[-+U]?)(?<sha1>\w+)
+      \s(?<path>[^\s]+?)
+      (?:\s\((?<describe>.+)\))?$
+    /x
+
+    # Struct encapsulating submodule information extracted from the
+    # output of `git submodule status`
+    SubmoduleStatus = Struct.new(:prefix, :sha1, :path, :describe) do
+      # Returns whether the submodule has not been initialized
+      def uninitialized?
+        prefix == '-'
+      end
+
+      # Returns whether the submodule is out of date with the current
+      # index, i.e. its checked-out commit differs from that stored in
+      # the index of the parent repo
+      def outdated?
+        prefix == '+'
+      end
+
+      # Returns whether the submodule reference has a merge conflict
+      def merge_conflict?
+        prefix == 'U'
+      end
+    end
+
+    # Returns a list of SubmoduleStatus objects, one for each submodule in the
+    # parent repository.
+    #
+    # @option options [Boolean] recursive check submodules recursively
+    # @return [Array<SubmoduleStatus>]
+    def submodule_statuses(options = {})
+      flags = '--recursive' if options[:recursive]
+
+      `git submodule status #{flags}`.
+        scan(SUBMODULE_STATUS_REGEX).
+        map do |prefix, sha1, path, describe|
+          SubmoduleStatus.new(prefix, sha1, path, describe)
+        end
+    end
+
     # Extract the set of modified lines from a given file.
     #
     # @param file_path [String]
diff --git a/lib/overcommit/hook/post_checkout/submodule_status.rb b/lib/overcommit/hook/post_checkout/submodule_status.rb
new file mode 100644
index 00000000..54648216
--- /dev/null
+++ b/lib/overcommit/hook/post_checkout/submodule_status.rb
@@ -0,0 +1,30 @@
+module Overcommit::Hook::PostCheckout
+  # Checks the status of submodules in the current repository and
+  # notifies the user if any are uninitialized, out of date with
+  # the current index, or contain merge conflicts.
+  class SubmoduleStatus < Base
+    def run
+      messages = []
+      submodule_statuses.each do |submodule_status|
+        path = submodule_status.path
+        if submodule_status.uninitialized?
+          messages << "Submodule #{path} is uninitialized."
+        elsif submodule_status.outdated?
+          messages << "Submodule #{path} is out of date with the current index."
+        elsif submodule_status.merge_conflict?
+          messages << "Submodule #{path} has merge conflicts."
+        end
+      end
+
+      return :pass if messages.empty?
+
+      [:warn, messages.join("\n")]
+    end
+
+    private
+
+    def submodule_statuses
+      Overcommit::GitRepo.submodule_statuses(recursive: config['recursive'])
+    end
+  end
+end
diff --git a/lib/overcommit/hook/post_commit/submodule_status.rb b/lib/overcommit/hook/post_commit/submodule_status.rb
new file mode 100644
index 00000000..1648768a
--- /dev/null
+++ b/lib/overcommit/hook/post_commit/submodule_status.rb
@@ -0,0 +1,30 @@
+module Overcommit::Hook::PostCommit
+  # Checks the status of submodules in the current repository and
+  # notifies the user if any are uninitialized, out of date with
+  # the current index, or contain merge conflicts.
+  class SubmoduleStatus < Base
+    def run
+      messages = []
+      submodule_statuses.each do |submodule_status|
+        path = submodule_status.path
+        if submodule_status.uninitialized?
+          messages << "Submodule #{path} is uninitialized."
+        elsif submodule_status.outdated?
+          messages << "Submodule #{path} is out of date with the current index."
+        elsif submodule_status.merge_conflict?
+          messages << "Submodule #{path} has merge conflicts."
+        end
+      end
+
+      return :pass if messages.empty?
+
+      [:warn, messages.join("\n")]
+    end
+
+    private
+
+    def submodule_statuses
+      Overcommit::GitRepo.submodule_statuses(recursive: config['recursive'])
+    end
+  end
+end
diff --git a/lib/overcommit/hook/post_merge/submodule_status.rb b/lib/overcommit/hook/post_merge/submodule_status.rb
new file mode 100644
index 00000000..979327ff
--- /dev/null
+++ b/lib/overcommit/hook/post_merge/submodule_status.rb
@@ -0,0 +1,30 @@
+module Overcommit::Hook::PostMerge
+  # Checks the status of submodules in the current repository and
+  # notifies the user if any are uninitialized, out of date with
+  # the current index, or contain merge conflicts.
+  class SubmoduleStatus < Base
+    def run
+      messages = []
+      submodule_statuses.each do |submodule_status|
+        path = submodule_status.path
+        if submodule_status.uninitialized?
+          messages << "Submodule #{path} is uninitialized."
+        elsif submodule_status.outdated?
+          messages << "Submodule #{path} is out of date with the current index."
+        elsif submodule_status.merge_conflict?
+          messages << "Submodule #{path} has merge conflicts."
+        end
+      end
+
+      return :pass if messages.empty?
+
+      [:warn, messages.join("\n")]
+    end
+
+    private
+
+    def submodule_statuses
+      Overcommit::GitRepo.submodule_statuses(recursive: config['recursive'])
+    end
+  end
+end
diff --git a/lib/overcommit/hook/post_rewrite/submodule_status.rb b/lib/overcommit/hook/post_rewrite/submodule_status.rb
new file mode 100644
index 00000000..8e79a16f
--- /dev/null
+++ b/lib/overcommit/hook/post_rewrite/submodule_status.rb
@@ -0,0 +1,30 @@
+module Overcommit::Hook::PostRewrite
+  # Checks the status of submodules in the current repository and
+  # notifies the user if any are uninitialized, out of date with
+  # the current index, or contain merge conflicts.
+  class SubmoduleStatus < Base
+    def run
+      messages = []
+      submodule_statuses.each do |submodule_status|
+        path = submodule_status.path
+        if submodule_status.uninitialized?
+          messages << "Submodule #{path} is uninitialized."
+        elsif submodule_status.outdated?
+          messages << "Submodule #{path} is out of date with the current index."
+        elsif submodule_status.merge_conflict?
+          messages << "Submodule #{path} has merge conflicts."
+        end
+      end
+
+      return :pass if messages.empty?
+
+      [:warn, messages.join("\n")]
+    end
+
+    private
+
+    def submodule_statuses
+      Overcommit::GitRepo.submodule_statuses(recursive: config['recursive'])
+    end
+  end
+end
diff --git a/spec/overcommit/hook/post_checkout/submodule_status_spec.rb b/spec/overcommit/hook/post_checkout/submodule_status_spec.rb
new file mode 100644
index 00000000..45078f46
--- /dev/null
+++ b/spec/overcommit/hook/post_checkout/submodule_status_spec.rb
@@ -0,0 +1,54 @@
+require 'spec_helper'
+
+describe Overcommit::Hook::PostCheckout::SubmoduleStatus do
+  let(:config)  { Overcommit::ConfigurationLoader.default_configuration }
+  let(:context) { double('context') }
+  subject { described_class.new(config, context) }
+
+  let(:submodule_status) { double('submodule_status') }
+
+  before do
+    submodule_status.stub(:path).and_return('sub')
+    subject.stub(:submodule_statuses).and_return([submodule_status])
+  end
+
+  context 'when submodule is up to date' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should pass }
+  end
+
+  context 'when submodule is uninitialized' do
+    before do
+      submodule_status.stub(uninitialized?: true,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/uninitialized/) }
+  end
+
+  context 'when submodule is outdated' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: true,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/out of date/) }
+  end
+
+  context 'when submodule has merge conflicts' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: true)
+    end
+
+    it { should warn(/merge conflicts/) }
+  end
+end
diff --git a/spec/overcommit/hook/post_commit/submodule_status_spec.rb b/spec/overcommit/hook/post_commit/submodule_status_spec.rb
new file mode 100644
index 00000000..2c12d5fe
--- /dev/null
+++ b/spec/overcommit/hook/post_commit/submodule_status_spec.rb
@@ -0,0 +1,54 @@
+require 'spec_helper'
+
+describe Overcommit::Hook::PostCommit::SubmoduleStatus do
+  let(:config)  { Overcommit::ConfigurationLoader.default_configuration }
+  let(:context) { double('context') }
+  subject { described_class.new(config, context) }
+
+  let(:submodule_status) { double('submodule_status') }
+
+  before do
+    submodule_status.stub(:path).and_return('sub')
+    subject.stub(:submodule_statuses).and_return([submodule_status])
+  end
+
+  context 'when submodule is up to date' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should pass }
+  end
+
+  context 'when submodule is uninitialized' do
+    before do
+      submodule_status.stub(uninitialized?: true,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/uninitialized/) }
+  end
+
+  context 'when submodule is outdated' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: true,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/out of date/) }
+  end
+
+  context 'when submodule has merge conflicts' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: true)
+    end
+
+    it { should warn(/merge conflicts/) }
+  end
+end
diff --git a/spec/overcommit/hook/post_merge/submodule_status_spec.rb b/spec/overcommit/hook/post_merge/submodule_status_spec.rb
new file mode 100644
index 00000000..245fe6c1
--- /dev/null
+++ b/spec/overcommit/hook/post_merge/submodule_status_spec.rb
@@ -0,0 +1,54 @@
+require 'spec_helper'
+
+describe Overcommit::Hook::PostMerge::SubmoduleStatus do
+  let(:config)  { Overcommit::ConfigurationLoader.default_configuration }
+  let(:context) { double('context') }
+  subject { described_class.new(config, context) }
+
+  let(:submodule_status) { double('submodule_status') }
+
+  before do
+    submodule_status.stub(:path).and_return('sub')
+    subject.stub(:submodule_statuses).and_return([submodule_status])
+  end
+
+  context 'when submodule is up to date' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should pass }
+  end
+
+  context 'when submodule is uninitialized' do
+    before do
+      submodule_status.stub(uninitialized?: true,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/uninitialized/) }
+  end
+
+  context 'when submodule is outdated' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: true,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/out of date/) }
+  end
+
+  context 'when submodule has merge conflicts' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: true)
+    end
+
+    it { should warn(/merge conflicts/) }
+  end
+end
diff --git a/spec/overcommit/hook/post_rewrite/submodule_status_spec.rb b/spec/overcommit/hook/post_rewrite/submodule_status_spec.rb
new file mode 100644
index 00000000..c783c029
--- /dev/null
+++ b/spec/overcommit/hook/post_rewrite/submodule_status_spec.rb
@@ -0,0 +1,54 @@
+require 'spec_helper'
+
+describe Overcommit::Hook::PostRewrite::SubmoduleStatus do
+  let(:config)  { Overcommit::ConfigurationLoader.default_configuration }
+  let(:context) { double('context') }
+  subject { described_class.new(config, context) }
+
+  let(:submodule_status) { double('submodule_status') }
+
+  before do
+    submodule_status.stub(:path).and_return('sub')
+    subject.stub(:submodule_statuses).and_return([submodule_status])
+  end
+
+  context 'when submodule is up to date' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should pass }
+  end
+
+  context 'when submodule is uninitialized' do
+    before do
+      submodule_status.stub(uninitialized?: true,
+                            outdated?: false,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/uninitialized/) }
+  end
+
+  context 'when submodule is outdated' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: true,
+                            merge_conflict?: false)
+    end
+
+    it { should warn(/out of date/) }
+  end
+
+  context 'when submodule has merge conflicts' do
+    before do
+      submodule_status.stub(uninitialized?: false,
+                            outdated?: false,
+                            merge_conflict?: true)
+    end
+
+    it { should warn(/merge conflicts/) }
+  end
+end