diff --git a/src/format.rs b/src/format.rs
index e85e4d8c5..139ca02ca 100644
--- a/src/format.rs
+++ b/src/format.rs
@@ -144,4 +144,23 @@ mod tests {
             assert_eq!(url.to_string(), result.to_string());
         }
     }
+
+    #[test]
+    fn authorities() {
+        let data = [
+            ("http://example.com/", "example.com"),
+            ("http://noslash.com", "noslash.com"),
+            ("http://@emptyuser.com/", "emptyuser.com"),
+            ("http://:@emptypass.com/", ":@emptypass.com"),
+            ("http://user@user.com/", "user@user.com"),
+            ("http://user:pass@userpass.com/", "user:pass@userpass.com"),
+            ("http://host.com:8080/path", "host.com:8080"),
+            ("http://user:pass@host.com:8080/path", "user:pass@host.com:8080"),
+        ];
+        for &(input, result) in data.iter() {
+            let url = Url::parse(input).unwrap();
+            let auth = url.authority().unwrap();
+            assert_eq!(auth.to_string(), result.to_string());
+        }
+    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 779b85589..7b2e67f9e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -247,6 +247,40 @@ pub struct RelativeSchemeData {
     pub path: Vec<String>,
 }
 
+/// The Authority part of a URI.
+pub struct Authority<'a> {
+    username: Option<&'a str>,
+    password: Option<&'a str>,
+    host: Option<&'a Host>,
+    port: Option<u16>
+}
+
+impl<'a> Show for Authority<'a> {
+    fn fmt(&self, fmt: &mut Formatter) -> Result<(), FormatError> {
+        match self.username {
+            Some(ref u) => {
+                try!(UserInfoFormatter {
+                    username: *u,
+                    password: self.password
+                }.fmt(fmt));
+            },
+            None => ()
+        }
+        match self.host {
+            Some(ref h) => try!(h.fmt(fmt)),
+            None => ()
+        }
+        match self.port {
+            Some(ref p) => {
+                try!(':'.fmt(fmt));
+                try!(p.fmt(fmt));
+            },
+            None => ()
+        }
+        Ok(())
+    }
+}
+
 impl<S: hash::Writer> hash::Hash<S> for Url {
     fn hash(&self, state: &mut S) {
         self.serialize().hash(state)
@@ -554,6 +588,17 @@ impl Url {
         }
     }
 
+    /// If the URL is in a *relative scheme*, return its Authority.
+    #[inline]
+    pub fn authority<'a>(&'a self) -> Option<Authority<'a>> {
+        self.relative_scheme_data().and(Some(Authority {
+            username: self.username(),
+            password: self.password(),
+            host: self.host(),
+            port: self.port()
+        }))
+    }
+
     /// If the URL is in a *relative scheme*, return its username.
     #[inline]
     pub fn username<'a>(&'a self) -> Option<&'a str> {