diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index 47cf759..de2660a 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+from __future__ import print_function
+
 import copy
 import errno
 import getopt
@@ -34,6 +36,17 @@
 
 from hashlib import sha1 as sha1
 
+try:
+  raw_input
+except NameError:
+  raw_input = input
+
+
+def iteritems(obj):
+  if hasattr(obj, 'iteritems'):
+    return obj.iteritems()
+  return obj.items()
+
 
 class Options(object):
   def __init__(self):
@@ -83,7 +96,7 @@
   """Create and return a subprocess.Popen object, printing the command
   line on the terminal if -v was specified."""
   if OPTIONS.verbose:
-    print "  running: ", " ".join(args)
+    print("  running: ", " ".join(args))
   return subprocess.Popen(args, **kwargs)
 
 
@@ -193,7 +206,7 @@
   try:
     data = read_helper("SYSTEM/build.prop")
   except KeyError:
-    print "Warning: could not find SYSTEM/build.prop in %s" % zip
+    print("Warning: could not find SYSTEM/build.prop in %s" % zip)
     data = ""
   return LoadDictionaryFromLines(data.split("\n"))
 
@@ -221,7 +234,7 @@
   try:
     data = read_helper("RECOVERY/RAMDISK/etc/recovery.fstab")
   except KeyError:
-    print "Warning: could not find RECOVERY/RAMDISK/etc/recovery.fstab"
+    print("Warning: could not find RECOVERY/RAMDISK/etc/recovery.fstab")
     data = ""
 
   if fstab_version == 1:
@@ -253,7 +266,7 @@
           if i.startswith("length="):
             length = int(i[7:])
           else:
-            print "%s: unknown option \"%s\"" % (mount_point, i)
+            print("%s: unknown option \"%s\"" % (mount_point, i))
 
       d[mount_point] = Partition(mount_point=mount_point, fs_type=pieces[1],
                                  device=pieces[2], length=length,
@@ -305,7 +318,7 @@
 
 def DumpInfoDict(d):
   for k, v in sorted(d.items()):
-    print "%-25s = (%s) %s" % (k, type(v).__name__, v)
+    print("%-25s = (%s) %s" % (k, type(v).__name__, v))
 
 
 def BuildBootableImage(sourcedir, fs_config_file, info_dict=None):
@@ -459,15 +472,15 @@
 
   prebuilt_path = os.path.join(unpack_dir, "BOOTABLE_IMAGES", prebuilt_name)
   if os.path.exists(prebuilt_path):
-    print "using prebuilt %s from BOOTABLE_IMAGES..." % (prebuilt_name,)
+    print("using prebuilt %s from BOOTABLE_IMAGES..." % prebuilt_name)
     return File.FromLocalFile(name, prebuilt_path)
 
   prebuilt_path = os.path.join(unpack_dir, "IMAGES", prebuilt_name)
   if os.path.exists(prebuilt_path):
-    print "using prebuilt %s from IMAGES..." % (prebuilt_name,)
+    print("using prebuilt %s from IMAGES..." % prebuilt_name)
     return File.FromLocalFile(name, prebuilt_path)
 
-  print "building image from target_files %s..." % (tree_subdir,)
+  print("building image from target_files %s..." % tree_subdir)
   fs_config = "META/" + tree_subdir.lower() + "_filesystem_config.txt"
   data = BuildBootableImage(os.path.join(unpack_dir, tree_subdir),
                             os.path.join(unpack_dir, fs_config),
@@ -546,7 +559,7 @@
       if p.returncode == 0:
         # Encrypted key with empty string as password.
         key_passwords[k] = ''
-      elif stderr.startswith('Error decrypting key'):
+      elif stderr.startswith(b'Error decrypting key'):
         # Definitely encrypted key.
         # It would have said "Error reading key" if it didn't parse correctly.
         need_passwords.append(k)
@@ -641,11 +654,11 @@
   if pct >= 99.0:
     raise ExternalError(msg)
   elif pct >= 95.0:
-    print
-    print "  WARNING: ", msg
-    print
+    print()
+    print("  WARNING: ", msg)
+    print()
   elif OPTIONS.verbose:
-    print "  ", msg
+    print("  ", msg)
 
 
 def ReadApkCerts(tf_zip):
@@ -694,8 +707,8 @@
 """
 
 def Usage(docstring):
-  print docstring.rstrip("\n")
-  print COMMON_DOCSTRING
+  print(docstring.rstrip("\n"))
+  print(COMMON_DOCSTRING)
 
 
 def ParseOptions(argv,
@@ -719,7 +732,7 @@
         list(extra_long_opts))
   except getopt.GetoptError as err:
     Usage(docstring)
-    print "**", str(err), "**"
+    print("**", str(err), "**")
     sys.exit(2)
 
   for o, a in opts:
@@ -815,7 +828,7 @@
         current[i] = ""
 
       if not first:
-        print "key file %s still missing some passwords." % (self.pwfile,)
+        print("key file %s still missing some passwords." % self.pwfile)
         answer = raw_input("try to edit again? [y]> ").strip()
         if answer and answer[0] not in 'yY':
           raise RuntimeError("key passwords unavailable")
@@ -829,7 +842,7 @@
     values.
     """
     result = {}
-    for k, v in sorted(current.iteritems()):
+    for k, v in sorted(iteritems(current)):
       if v:
         result[k] = v
       else:
@@ -850,7 +863,7 @@
     f.write("# (Additional spaces are harmless.)\n\n")
 
     first_line = None
-    sorted_list = sorted([(not v, k, v) for (k, v) in current.iteritems()])
+    sorted_list = sorted((not v, k, v) for (k, v) in current.items())
     for i, (_, k, v) in enumerate(sorted_list):
       f.write("[[[  %s  ]]] %s\n" % (v, k))
       if not v and first_line is None:
@@ -875,13 +888,13 @@
           continue
         m = re.match(r"^\[\[\[\s*(.*?)\s*\]\]\]\s*(\S+)$", line)
         if not m:
-          print "failed to parse password file: ", line
+          print("failed to parse password file: ", line)
         else:
           result[m.group(2)] = m.group(1)
       f.close()
     except IOError as e:
       if e.errno != errno.ENOENT:
-        print "error reading password file: ", str(e)
+        print("error reading password file: ", str(e))
     return result
 
 
@@ -982,7 +995,7 @@
     """Keyword arguments to the constructor become attributes of this
     object, which is passed to all functions in the device-specific
     module."""
-    for k, v in kwargs.iteritems():
+    for k, v in iteritems(kwargs):
       setattr(self, k, v)
     self.extras = OPTIONS.extras
 
@@ -999,10 +1012,10 @@
           if x == ".py":
             f = b
           info = imp.find_module(f, [d])
-        print "loaded device-specific extensions from", path
+        print("loaded device-specific extensions from", path)
         self.module = imp.load_module("device_specific", *info)
       except ImportError:
-        print "unable to load device-specific module; assuming none"
+        print("unable to load device-specific module; assuming none")
 
   def _DoCall(self, function_name, *args, **kwargs):
     """Call the named function in the device-specific module, passing
@@ -1138,7 +1151,7 @@
       th.start()
       th.join(timeout=300)   # 5 mins
       if th.is_alive():
-        print "WARNING: diff command timed out"
+        print("WARNING: diff command timed out")
         p.terminate()
         th.join(5)
         if th.is_alive():
@@ -1146,8 +1159,8 @@
           th.join()
 
       if err or p.returncode != 0:
-        print "WARNING: failure running %s:\n%s\n" % (
-            diff_program, "".join(err))
+        print("WARNING: failure running %s:\n%s\n" % (
+            diff_program, "".join(err)))
         self.patch = None
         return None, None, None
       diff = ptemp.read()
@@ -1169,7 +1182,7 @@
 
 def ComputeDifferences(diffs):
   """Call ComputePatch on all the Difference objects in 'diffs'."""
-  print len(diffs), "diffs to compute"
+  print(len(diffs), "diffs to compute")
 
   # Do the largest files first, to try and reduce the long-pole effect.
   by_size = [(i.tf.size, i) for i in diffs]
@@ -1195,13 +1208,13 @@
         else:
           name = "%s (%s)" % (tf.name, sf.name)
         if patch is None:
-          print "patching failed!                                  %s" % (name,)
+          print("patching failed!                                  %s" % name)
         else:
-          print "%8.2f sec %8d / %8d bytes (%6.2f%%) %s" % (
-              dur, len(patch), tf.size, 100.0 * len(patch) / tf.size, name)
+          print("%8.2f sec %8d / %8d bytes (%6.2f%%) %s" % (
+              dur, len(patch), tf.size, 100.0 * len(patch) / tf.size, name))
       lock.release()
     except Exception as e:
-      print e
+      print(e)
       raise
 
   # start worker threads; wait for them all to finish.
@@ -1401,16 +1414,18 @@
 
 def ParseCertificate(data):
   """Parse a PEM-format certificate."""
+  from codecs import decode
   cert = []
   save = False
   for line in data.split("\n"):
     if "--END CERTIFICATE--" in line:
       break
     if save:
-      cert.append(line)
+      l = line.encode() if hasattr(line, 'encode') else line
+      cert.append(l)
     if "--BEGIN CERTIFICATE--" in line:
       save = True
-  cert = "".join(cert).decode('base64')
+  cert = decode(b"".join(cert), 'base64')
   return cert
 
 def MakeRecoveryPatch(input_dir, output_sink, recovery_img, boot_img,
@@ -1481,9 +1496,9 @@
         m = re.match(r"^service flash_recovery /system/(\S+)\s*$", line)
         if m:
           sh_location = m.group(1)
-          print "putting script in", sh_location
+          print("putting script in", sh_location)
           break
   except (OSError, IOError) as e:
-    print "failed to read init.rc: %s" % (e,)
+    print("failed to read init.rc: %s" % e)
 
   output_sink(sh_location, sh)