diff --git a/flee/src/lib.rs b/flee/src/lib.rs
index a615d4b..de2759c 100644
--- a/flee/src/lib.rs
+++ b/flee/src/lib.rs
@@ -65,20 +65,20 @@ fn split<'a, 'b>(s: &'a [u8], items: &'b [u8]) -> Split<'a, 'b> {
     Split(Some(s), items)
 }
 
-fn do_escape(s: &[u8], escaped_codes: &[u8], escape_token: u8) -> Vec<u8> {
+fn do_escape<'a>(s: &'a [u8], escaped_codes: &[u8], escape_token: u8) -> Cow<'a, [u8]> {
     match escaped_codes {
-        [] => s.to_vec(),
-        [first, rest @ ..] => join(
+        [] => Cow::Borrowed(s),
+        [first, rest @ ..] => Cow::Owned(join(
             split(s, &[*first]).map(|part| do_escape(part, rest, escape_token)),
             &[escape_token, *first],
-        ),
+        )),
     }
 }
 
 pub fn escape<'a>(s: &'a [u8], delimiter: u8, escape_token: u8) -> Cow<'a, [u8]> {
     let escaped_codes = &[escape_token, delimiter];
     if find_any(&s, escaped_codes).is_some() {
-        return Cow::Owned(do_escape(s, escaped_codes, escape_token));
+        return do_escape(s, escaped_codes, escape_token);
     }
 
     Cow::Borrowed(s)