diff --git a/CHANGELOG.md b/CHANGELOG.md
index 53c94b5..0c52639 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,30 @@
-# List of changes
+# Changelog
+All notable changes in pdfminer.six will be documented in this file. 
 
-## Version 20181108
- - PR #141 to speedup layout analysis
- - PR #173 for using argparse and replace deprecated getopt
- - PR #142 to compile pdfminer.six with cython, successfully
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+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
+
+## [Unreleased]
+
+### Added
+- Contribution guidelines in [CONTRIBUTING.md](CONTRIBUTING.md) ([#259](https://github.com/pdfminer/pdfminer.six/pull/259))
+- Support new encodings OneByteEncoding and DLIdent for CMaps ([#283](https://github.com/pdfminer/pdfminer.six/pull/283))
+
+### Fixed
+- Use `six.iteritems()` instead of `dict().iteritems()` to ensure Python2 and Python3 compatibility ([#274](https://github.com/pdfminer/pdfminer.six/pull/274))
+- Properly convert Adobe Glyph names to unicode characters ([#263](https://github.com/pdfminer/pdfminer.six/pull/263))
+- Allow CMap to be a content stream ([#283](https://github.com/pdfminer/pdfminer.six/pull/283))
+- Resolve indirect objects for width and bounding boxes for fonts ([#273](https://github.com/pdfminer/pdfminer.six/pull/273))
+- Actually updating stroke color in graphic state ([#298](https://github.com/pdfminer/pdfminer.six/pull/298))
+- Interpret (invalid) negative font descent as a positive descent ([#203](https://github.com/pdfminer/pdfminer.six/pull/203))
+- Correct colorspace comparision for images ([#132](https://github.com/pdfminer/pdfminer.six/pull/132))
+- Allow for bounding boxes with zero height or width by removing assertion ([#246](https://github.com/pdfminer/pdfminer.six/pull/246))
+
+### Changed
+- All dependencies are managed in `setup.py` ([#306](https://github.com/pdfminer/pdfminer.six/pull/306), [#219](https://github.com/pdfminer/pdfminer.six/pull/219))
+
+## [20181108] - 2018-11-08
+
+### Changed
+- Speedup layout analysis ([#141](https://github.com/pdfminer/pdfminer.six/pull/141))
+- Use argparse instead of replace deprecated getopt ([#173](https://github.com/pdfminer/pdfminer.six/pull/173))
+- Allow pdfminer.six to be compiled with cython ([#142](https://github.com/pdfminer/pdfminer.six/pull/142))
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