diff --git a/changelog.d/17069.doc b/changelog.d/17069.doc
new file mode 100644
index 0000000000000000000000000000000000000000..f5a7f599d14d48f8437982f95a39289a70b06e79
--- /dev/null
+++ b/changelog.d/17069.doc
@@ -0,0 +1 @@
+Add a prompt in the contributing guide to manually configure icu4c.
diff --git a/docs/development/contributing_guide.md b/docs/development/contributing_guide.md
index ac8a7039d18e844bf4e65e8c86003accfe573313..76c3e790cd81a415f8158959ee87cf8d9e06cc5d 100644
--- a/docs/development/contributing_guide.md
+++ b/docs/development/contributing_guide.md
@@ -86,6 +86,8 @@ poetry install --extras all
 This will install the runtime and developer dependencies for the project.  Be sure to check
 that the `poetry install` step completed cleanly.
 
+For OSX users, be sure to set `PKG_CONFIG_PATH` to support `icu4c`. Run `brew info icu4c` for more details.
+
 ## Running Synapse via poetry
 
 To start a local instance of Synapse in the locked poetry environment, create a config file: