diff --git a/pubs/commands/edit_cmd.py b/pubs/commands/edit_cmd.py
index 30ab5e8..d563dc6 100644
--- a/pubs/commands/edit_cmd.py
+++ b/pubs/commands/edit_cmd.py
@@ -3,7 +3,7 @@ from .. import repo
 from ..configs import config
 from ..uis import get_ui
 from ..endecoder import EnDecoder
-
+from ..utils import resolve_citekey
 
 def parser(subparsers):
     parser = subparsers.add_parser('edit',
@@ -19,14 +19,10 @@ def command(args):
 
     ui = get_ui()
     meta = args.meta
-    citekey = args.citekey
 
     rp = repo.Repository(config())
-    try:
-        paper = rp.pull_paper(citekey)
-    except repo.InvalidReference as v:
-        ui.error(v)
-        ui.exit(1)
+    citekey = resolve_citekey(rp, args.citekey, ui=ui, exit_on_fail=True)
+    paper = rp.pull_paper(citekey)
 
     coder = EnDecoder()
     if meta:
diff --git a/pubs/commands/open_cmd.py b/pubs/commands/open_cmd.py
index ccbc040..5a1f589 100644
--- a/pubs/commands/open_cmd.py
+++ b/pubs/commands/open_cmd.py
@@ -5,7 +5,7 @@ from ..configs import config
 from ..uis import get_ui
 from .. import color
 from ..content import system_path
-
+from ..utils import resolve_citekey
 
 def parser(subparsers):
     parser = subparsers.add_parser('open',
@@ -21,10 +21,11 @@ def command(args):
 
     ui = get_ui()
     with_command = args.with_command
-    citekey = args.citekey
 
     rp = repo.Repository(config())
+    citekey = resolve_citekey(rp, args.citekey, ui=ui, exit_on_fail=True)
     paper = rp.pull_paper(citekey)
+
     if with_command is None:
         with_command = config().open_cmd
 
diff --git a/pubs/repo.py b/pubs/repo.py
index 2873f51..5953c3b 100644
--- a/pubs/repo.py
+++ b/pubs/repo.py
@@ -50,6 +50,11 @@ class Repository(object):
         for key in self.citekeys:
             yield self.pull_paper(key)
 
+    def citekeys_from_prefix(self, prefix):
+        """Return all citekey beginning with prefix."""
+        return tuple(citekey for citekey in self.citekeys
+                     if citekey.startswith(prefix))
+
     def pull_paper(self, citekey):
         """Load a paper by its citekey from disk, if necessary."""
         if citekey in self:
diff --git a/pubs/uis.py b/pubs/uis.py
index a01ad52..441dfb0 100644
--- a/pubs/uis.py
+++ b/pubs/uis.py
@@ -89,7 +89,7 @@ class UI:
                 if default is not None:
                     return default
             else:
-                try:
+                try: # FIXME options handling !!!
                     return option_chars.index(answer.lower())
                 except ValueError:
                     pass
diff --git a/pubs/utils.py b/pubs/utils.py
new file mode 100644
index 0000000..7a9f934
--- /dev/null
+++ b/pubs/utils.py
@@ -0,0 +1,24 @@
+# Function here may belong somewhere else. In the mean time...
+
+def resolve_citekey(repo, citekey, ui=None, exit_on_fail=True):
+    """Check that a citekey exists, or autocompletes it if not ambiguous."""
+    # FIXME. Make me optionally non ui interactive/exiting
+    citekeys = repo.citekeys_from_prefix(citekey)
+    if len(citekeys) == 0:
+        if ui is not None:
+            ui.error("No citekey named or beginning with '{}".format(citekey))
+            if exit_on_fail:
+                ui.exit()
+    elif len(citekeys) == 1:
+        if citekeys[0] != citekey:
+            if ui is not None:
+                ui.print_("Provided citekey '{}' has been autocompleted into '{}'".format(citekey, citekeys[0]))
+            citekey = citekeys[0]
+    elif citekey not in citekeys:
+        if ui is not None:
+            ui.error("Be more specific. Provided citekey '{}' matches multiples citekeys: {}".format(citekey, ', '.join(citekeys)))
+            if exit_on_fail:
+                ui.exit()
+    return citekey
+
+