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diff --git a/README.md b/README.md
index 1e6e66d..49ab445 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,9 @@ Enum-like behavior for Ruby, heavily inspired by [this](http://www.rubyfleebie.c
     - [Mapping values to keys](#mapping-values-to-keys)
   - [Duplicate enumerator keys or duplicate values](#duplicate-enumerator-keys-or-duplicate-values)
   - [Inheritance](#inheritance)
+  - [Exhaustive case matcher](#exhaustive-case-matcher)
+  - [I18n support](#i18n-support)
+- [Benchmarks](#benchmarks)
 - [Contributing](#contributing)
 - [Copyright and License](#copyright-and-license)
 - [Related Projects](#related-projects)
@@ -259,6 +262,62 @@ OrderState.values # ['CREATED', 'PAID']
 ShippedOrderState.values # ['CREATED', 'PAID', 'PREPARED', SHIPPED']
 ```
 
+### Exhaustive case matcher
+
+If you want to make sure that you cover all cases in a case stament, you can use the exhaustive case matcher: `Ruby::Enum::Case`. It will raise an error if a case/enum value is not handled, or if a value is specified that's not part of the enum. This is inspired by the [Rust Pattern Syntax](https://doc.rust-lang.org/book/ch18-03-pattern-syntax.html). If multiple cases match, all matches are being executed. The return value is the value from the matched case, or an array of return values if multiple cases matched.
+
+> NOTE: This will add checks at runtime which might lead to worse performance. See [benchmarks](#benchmarks).
+
+> NOTE: `:else` is a reserved keyword if you want to use `Ruby::Enum::Case`.
+
+```ruby
+class Color < OrderState
+  include Ruby::Enum
+  include Ruby::Enum::Case
+
+  define :RED, :red
+  define :GREEN, :green
+  define :BLUE, :blue
+  define :YELLOW, :yellow
+end
+```
+
+```ruby
+color = Color::RED
+Color.Case(color, {
+  [Color::GREEN, Color::BLUE] => -> { "order is green or blue" },
+  Color::YELLOW => -> { "order is yellow" },
+  Color::RED => -> { "order is red" },
+})
+```
+
+It also supports default/else:
+
+```ruby
+color = Color::RED
+Color.Case(color, {
+  [Color::GREEN, Color::BLUE] => -> { "order is green or blue" },
+  else: -> { "order is yellow or red" },
+})
+```
+
+### I18n support
+
+This gem has an optional dependency to `i18n`. If it's available, the error messages will have a nice description and can be translated. If it's not available, the errors will only contain the message keys.
+
+```ruby
+# Add this to your Gemfile if you want to have a nice error description instead of just a message key.
+gem "i18n"
+```
+
+## Benchmarks
+
+Benchmark scripts are defined in the [`benchmarks`](benchmarks) folder and can be run with Rake:
+
+```console
+rake benchmarks:case
+```
+
 ## Contributing
 
 You're encouraged to contribute to ruby-enum. See [CONTRIBUTING](CONTRIBUTING.md) for details.