diff --git a/src/form_urlencoded.rs b/src/form_urlencoded.rs
index 78272c7c..9464156d 100644
--- a/src/form_urlencoded.rs
+++ b/src/form_urlencoded.rs
@@ -13,6 +13,7 @@
 //! Converts between a string (such as an URL’s query string)
 //! and a sequence of (name, value) pairs.
 
+use std::ascii::AsciiExt;
 use encoding::EncodingOverride;
 use percent_encoding::{percent_encode_to, percent_decode, FORM_URLENCODED_ENCODE_SET};
 
diff --git a/src/host.rs b/src/host.rs
index f109ccb5..82b61b83 100644
--- a/src/host.rs
+++ b/src/host.rs
@@ -6,7 +6,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use std::ascii::OwnedAsciiExt;
+use std::ascii::{AsciiExt, OwnedAsciiExt};
 use std::cmp;
 use std::fmt::{mod, Formatter, Show};
 use parser::{ParseResult, ParseError};
@@ -63,7 +63,7 @@ impl Host {
             ].as_slice()).is_some() {
                 Err(ParseError::InvalidDomainCharacter)
             } else {
-                Ok(Host::Domain(domain.to_string().into_ascii_lower()))
+                Ok(Host::Domain(domain.to_string().into_ascii_lowercase()))
             }
         }
     }
diff --git a/src/parser.rs b/src/parser.rs
index b2ffbc53..7821c6ec 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -161,7 +161,7 @@ pub fn parse_scheme<'a>(input: &'a str, context: Context) -> Option<(String, &'a
         match c {
             'a'...'z' | 'A'...'Z' | '0'...'9' | '+' | '-' | '.' => (),
             ':' => return Some((
-                input.slice_to(i).to_ascii_lower(),
+                input.slice_to(i).to_ascii_lowercase(),
                 input.slice_from(i + 1),
             )),
             _ => return None,
@@ -169,7 +169,7 @@ pub fn parse_scheme<'a>(input: &'a str, context: Context) -> Option<(String, &'a
     }
     // EOF before ':'
     match context {
-        Context::Setter => Some((input.to_ascii_lower(), "")),
+        Context::Setter => Some((input.to_ascii_lowercase(), "")),
         Context::UrlParser => None
     }
 }
diff --git a/src/punycode.rs b/src/punycode.rs
index c0efee7f..4555683e 100644
--- a/src/punycode.rs
+++ b/src/punycode.rs
@@ -15,6 +15,7 @@
 
 use std::u32;
 use std::char;
+use std::ascii::AsciiExt;
 
 // Bootstring parameters for Punycode
 static BASE: u32 = 36;