diff --git a/scripts/assemble_changelog.py b/scripts/assemble_changelog.py
new file mode 100755
index 0000000..91db793
--- /dev/null
+++ b/scripts/assemble_changelog.py
@@ -0,0 +1,241 @@
+#!/usr/bin/env python3
+
+"""Assemble Mbed Crypto change log entries into the change log file.
+"""
+
+# Copyright (C) 2019, Arm Limited, All Rights Reserved
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# This file is part of Mbed Crypto (https://tls.mbed.org)
+
+import argparse
+import glob
+import os
+import re
+import sys
+
+class InputFormatError(Exception):
+    def __init__(self, filename, line_number, message, *args, **kwargs):
+        self.filename = filename
+        self.line_number = line_number
+        self.message = message.format(*args, **kwargs)
+    def __str__(self):
+        return '{}:{}: {}'.format(self.filename, self.line_number, self.message)
+
+STANDARD_SECTIONS = (
+    b'Interface changes',
+    b'Default behavior changes',
+    b'Requirement changes',
+    b'New deprecations',
+    b'Removals',
+    b'New features',
+    b'Security',
+    b'Bug fixes',
+    b'Performance improvements',
+    b'Other changes',
+)
+
+class ChangeLog:
+    """An Mbed Crypto changelog.
+
+    A changelog is a file in Markdown format. Each level 2 section title
+    starts a version, and versions are sorted in reverse chronological
+    order. Lines with a level 2 section title must start with '##'.
+
+    Within a version, there are multiple sections, each devoted to a kind
+    of change: bug fix, feature request, etc. Section titles should match
+    entries in STANDARD_SECTIONS exactly.
+
+    Within each section, each separate change should be on a line starting
+    with a '*' bullet. There may be blank lines surrounding titles, but
+    there should not be any blank line inside a section.
+    """
+
+    _title_re = re.compile(br'#*')
+    def title_level(self, line):
+        """Determine whether the line is a title.
+
+        Return (level, content) where level is the Markdown section level
+        (1 for '#', 2 for '##', etc.) and content is the section title
+        without leading or trailing whitespace. For a non-title line,
+        the level is 0.
+        """
+        level = re.match(self._title_re, line).end()
+        return level, line[level:].strip()
+
+    def add_sections(self, *sections):
+        """Add the specified section titles to the list of known sections.
+
+        Sections will be printed back out in the order they were added.
+        """
+        for section in sections:
+            if section not in self.section_content:
+                self.section_list.append(section)
+                self.section_content[section] = []
+
+    def __init__(self, input_stream):
+        """Create a changelog object.
+
+        Read lines from input_stream, which is typically a file opened
+        for reading.
+        """
+        level_2_seen = 0
+        current_section = None
+        self.header = []
+        self.section_list = []
+        self.section_content = {}
+        self.add_sections(*STANDARD_SECTIONS)
+        self.trailer = []
+        for line in input_stream:
+            level, content = self.title_level(line)
+            if level == 2:
+                level_2_seen += 1
+                if level_2_seen <= 1:
+                    self.header.append(line)
+                else:
+                    self.trailer.append(line)
+            elif level == 3 and level_2_seen == 1:
+                current_section = content
+                self.add_sections(current_section)
+            elif level_2_seen == 1 and current_section != None:
+                if line.strip():
+                    self.section_content[current_section].append(line)
+            elif level_2_seen <= 1:
+                self.header.append(line)
+            else:
+                self.trailer.append(line)
+
+    def add_file(self, input_stream):
+        """Add changelog entries from a file.
+
+        Read lines from input_stream, which is typically a file opened
+        for reading. These lines must contain a series of level 3
+        Markdown sections with recognized titles. The corresponding
+        content is injected into the respective sections in the changelog.
+        The section titles must be either one of the hard-coded values
+        in assemble_changelog.py or already present in ChangeLog.md.
+        """
+        filename = input_stream.name
+        current_section = None
+        for line_number, line in enumerate(input_stream, 1):
+            if not line.strip():
+                continue
+            level, content = self.title_level(line)
+            if level == 3:
+                current_section = content
+                if current_section not in self.section_content:
+                    raise InputFormatError(filename, line_number,
+                                           'Section {} is not recognized',
+                                           str(current_section)[1:])
+            elif level == 0:
+                if current_section is None:
+                    raise InputFormatError(filename, line_number,
+                                           'Missing section title at the beginning of the file')
+                self.section_content[current_section].append(line)
+            else:
+                raise InputFormatError(filename, line_number,
+                                       'Only level 3 headers (###) are permitted')
+
+    def write(self, filename):
+        """Write the changelog to the specified file.
+        """
+        with open(filename, 'wb') as out:
+            for line in self.header:
+                out.write(line)
+            for section in self.section_list:
+                lines = self.section_content[section]
+                while lines and not lines[0].strip():
+                    del lines[0]
+                while lines and not lines[-1].strip():
+                    del lines[-1]
+                if not lines:
+                    continue
+                out.write(b'### ' + section + b'\n\n')
+                for line in lines:
+                    out.write(line)
+                out.write(b'\n')
+            for line in self.trailer:
+                out.write(line)
+
+def finish_output(files_to_remove, changelog, output_file):
+    """Write the changelog to the output file.
+
+    Remove the specified input files.
+    """
+    if os.path.exists(output_file) and not os.path.isfile(output_file):
+        # The output is a non-regular file (e.g. pipe). Write to it directly.
+        output_temp = output_file
+    else:
+        # The output is a regular file. Write to a temporary file,
+        # then move it into place atomically.
+        output_temp = output_file + '.tmp'
+    changelog.write(output_temp)
+    for filename in files_to_remove:
+        sys.stderr.write('Removing ' + filename + '\n')
+        #os.remove(filename)
+    if output_temp != output_file:
+        os.rename(output_temp, output_file)
+
+def merge_entries(options):
+    """Merge changelog entries into the changelog file.
+
+    Read the changelog file from options.input.
+    Read entries to merge from the directory options.dir.
+    Write the new changelog to options.output.
+    Remove the merged entries if options.keep_entries is false.
+    """
+    with open(options.input, 'rb') as input_file:
+        changelog = ChangeLog(input_file)
+    files_to_merge = glob.glob(os.path.join(options.dir, '*.md'))
+    if not files_to_merge:
+        sys.stderr.write('There are no pending changelog entries.\n')
+        return
+    for filename in files_to_merge:
+        with open(filename, 'rb') as input_file:
+            changelog.add_file(input_file)
+    files_to_remove = [] if options.keep_entries else files_to_merge
+    finish_output(files_to_remove, changelog, options.output)
+
+def set_defaults(options):
+    """Add default values for missing options."""
+    output_file = getattr(options, 'output', None)
+    if output_file is None:
+        options.output = options.input
+    if getattr(options, 'keep_entries', None) is None:
+        options.keep_entries = (output_file is not None)
+
+def main():
+    """Command line entry point."""
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument('--dir', '-d', metavar='DIR',
+                        default='ChangeLog.d',
+                        help='Directory to read entries from (default: ChangeLog.d)')
+    parser.add_argument('--input', '-i', metavar='FILE',
+                        default='ChangeLog.md',
+                        help='Existing changelog file to read from and augment (default: ChangeLog.md)')
+    parser.add_argument('--keep-entries',
+                        action='store_true', dest='keep_entries', default=None,
+                        help='Keep the files containing entries (default: remove them if --output/-o is not specified)')
+    parser.add_argument('--no-keep-entries',
+                        action='store_false', dest='keep_entries',
+                        help='Remove the files containing entries after they are merged (default: remove them if --output/-o is not specified)')
+    parser.add_argument('--output', '-o', metavar='FILE',
+                        help='Output changelog file (default: overwrite the input)')
+    options = parser.parse_args()
+    set_defaults(options)
+    merge_entries(options)
+
+if __name__ == '__main__':
+    main()