diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5c0cb74e..7a0d0651 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -56,7 +56,7 @@ set(QT_MODULES
 )
 
 set(Qt5_DIR ${CMAKE_BINARY_DIR}/../qt/qtbase/lib/cmake/Qt5 CACHE PATH "")
-find_package(Qt5 COMPONENTS ${QT_MODULES} REQUIRED)
+find_package(Qt5 5.9 COMPONENTS ${QT_MODULES} REQUIRED)
 
 add_subdirectory(dep)
 add_subdirectory(src)
diff --git a/README.md b/README.md
index 07e9d686..311574f4 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,7 @@ by system libraries.
 
 **External Dependencies**
 
-* Qt (required, version 5.12+ is recommended)
+* Qt (required >= 5.9)
 
 **Included Dependencies**
 
@@ -106,9 +106,9 @@ your contributions under the terms of the license.
 Contribute by following the typical
 [GitHub workflow](https://guides.github.com/introduction/flow/index.html)
 for pull requests. Fork the repository and make changes on a new named
-branch. Create pull requests against the `master` branch. Follow the 
-[seven guidlines](https://chris.beams.io/posts/git-commit/) to writing a great 
-commit message.
+branch. Create pull requests against the `master` branch. Follow the
+[seven guidelines](https://chris.beams.io/posts/git-commit/) to writing a
+great commit message.
 
 License
 -------