diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 00000000..adbf367f
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,21 @@
+# This is the project top-level .editorconfig
+root = true
+
+# Defaults for all file types
+[*]
+# 4-space indents, no TABs
+indent_style = space
+tab_width = 4
+indent_size = tab
+
+# Hard-wrap at 120 columns
+max_line_length = 119
+
+# Windows EOL, for historical reasons
+end_of_line = crlf
+
+# UTF-8 is the only sensible option, no BOM
+charset = utf-8
+
+# All files should have a final newline
+insert_final_newline = true
diff --git a/Contributing.md b/Contributing.md
index 0b1f4d58..e61fe764 100644
--- a/Contributing.md
+++ b/Contributing.md
@@ -23,6 +23,16 @@ consistent with our vision for EDMC. Fundamental changes in particular need to b
 
 ---
 
+## Text formatting
+
+The project contains an `.editorconfig` file at its root.  Please either ensure
+your editor is taking note of those settings, or cross-check its contents
+with the
+[editorconfig documentation](https://github.com/editorconfig/editorconfig/wiki/EditorConfig-Properties)
+, and ensure your editor/IDE's settings match.
+
+---
+
 ## General workflow
 
 1. You will need a GitHub account.