diff --git a/mepo.d/cmdline/parser.py b/mepo.d/cmdline/parser.py
index 0db5d8f..cf36af6 100644
--- a/mepo.d/cmdline/parser.py
+++ b/mepo.d/cmdline/parser.py
@@ -100,7 +100,15 @@ def __diff(self):
         diff = self.subparsers.add_parser(
             'diff',
             description = 'Diff all components')
-        diff.add_argument('--name-only', action = 'store_true', help = 'Show only names of changed files')
+        diff.add_argument(
+            '--name-only',
+            action = 'store_true',
+            help = 'Show only names of changed files')
+        diff.add_argument(
+            'comp_name',
+            metavar = 'comp-name',
+            nargs = '*',
+            help = 'Component to list branches in')
 
     def __checkout(self):
         checkout = self.subparsers.add_parser(
diff --git a/mepo.d/command/diff/diff.py b/mepo.d/command/diff/diff.py
index 5362e70..8f73e4d 100644
--- a/mepo.d/command/diff/diff.py
+++ b/mepo.d/command/diff/diff.py
@@ -6,18 +6,28 @@
 from state.state import MepoState
 from repository.git import GitRepository
 from utilities.version import version_to_string
+from utilities import verify
 
 from shutil import get_terminal_size
 
 def run(args):
     print('Diffing...'); sys.stdout.flush()
+
     allcomps = MepoState.read_state()
+    comps2diff = _get_comps_to_diff(args.comp_name, allcomps)
 
-    for comp in allcomps:
+    for comp in comps2diff:
         result = check_component_diff(comp, args)
         if result:
             print_diff(comp, args, result)
 
+def _get_comps_to_diff(specified_comps, allcomps):
+    comps_to_diff = allcomps
+    if specified_comps:
+        verify.valid_components(specified_comps, allcomps)
+        comps_to_diff = [x for x in allcomps if x.name in specified_comps]
+    return comps_to_diff
+
 def check_component_diff(comp, args):
     git = GitRepository(comp.remote, comp.local)
     return git.run_diff(args)