diff --git a/CHANGES.md b/CHANGES.md
index f9d2eb64..04adff50 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -3,6 +3,8 @@
 
 - Improve error message if image shapes don't match. [#79]
 
+- Properly register mpl_image_compare marker with pytest. [#83]
+
 0.10 (2018-09-25)
 -----------------
 
diff --git a/pytest_mpl/plugin.py b/pytest_mpl/plugin.py
index a57ee040..8096f93e 100644
--- a/pytest_mpl/plugin.py
+++ b/pytest_mpl/plugin.py
@@ -104,6 +104,8 @@ def pytest_addoption(parser):
 
 def pytest_configure(config):
 
+    config.addinivalue_line('markers', "mpl_image_compare: Compares matplotlib figures against a baseline image")
+
     if config.getoption("--mpl") or config.getoption("--mpl-generate-path") is not None:
 
         baseline_dir = config.getoption("--mpl-baseline-path")