diff --git a/tests/client.rs b/tests/client.rs
index 541f1ba..a302a2a 100644
--- a/tests/client.rs
+++ b/tests/client.rs
@@ -79,9 +79,9 @@ fn test_post() {
         request: b"\
             POST /2 HTTP/1.1\r\n\
             Host: $HOST\r\n\
-            Content-Length: 5\r\n\
             User-Agent: $USERAGENT\r\n\
             Accept: */*\r\n\
+            Content-Length: 5\r\n\
             Accept-Encoding: gzip\r\n\
             \r\n\
             Hello\
@@ -170,3 +170,111 @@ fn test_error_for_status_5xx() {
     assert!(err.is_server_error());
     assert_eq!(err.status(), Some(reqwest::StatusCode::InternalServerError));
 }
+
+#[test]
+fn test_default_headers() {
+    use reqwest::header;
+    let mut headers = header::Headers::with_capacity(1);
+    let mut cookies = header::Cookie::new();
+    cookies.set("a", "b");
+    cookies.set("c", "d");
+    headers.set(cookies);
+    let client = reqwest::Client::builder()
+        .default_headers(headers)
+        .build().unwrap();
+
+    let server = server! {
+        request: b"\
+            GET /1 HTTP/1.1\r\n\
+            Host: $HOST\r\n\
+            User-Agent: $USERAGENT\r\n\
+            Accept: */*\r\n\
+            Cookie: a=b; c=d\r\n\
+            Accept-Encoding: gzip\r\n\
+            \r\n\
+            ",
+        response: b"\
+            HTTP/1.1 200 OK\r\n\
+            Server: test\r\n\
+            Content-Length: 0\r\n\
+            \r\n\
+            "
+    };
+
+    let url = format!("http://{}/1", server.addr());
+    let res = client.get(&url).send().unwrap();
+
+    assert_eq!(res.url().as_str(), &url);
+    assert_eq!(res.status(), reqwest::StatusCode::Ok);
+    assert_eq!(res.headers().get(),
+               Some(&reqwest::header::Server::new("test")));
+    assert_eq!(res.headers().get(),
+               Some(&reqwest::header::ContentLength(0)));
+
+    let server = server! {
+        request: b"\
+            GET /2 HTTP/1.1\r\n\
+            Host: $HOST\r\n\
+            User-Agent: $USERAGENT\r\n\
+            Accept: */*\r\n\
+            Cookie: a=b; c=d\r\n\
+            Accept-Encoding: gzip\r\n\
+            \r\n\
+            ",
+        response: b"\
+            HTTP/1.1 200 OK\r\n\
+            Server: test\r\n\
+            Content-Length: 0\r\n\
+            \r\n\
+            "
+    };
+
+    let url = format!("http://{}/2", server.addr());
+    let res = client.get(&url).send().unwrap();
+
+    assert_eq!(res.url().as_str(), &url);
+    assert_eq!(res.status(), reqwest::StatusCode::Ok);
+    assert_eq!(res.headers().get(),
+               Some(&reqwest::header::Server::new("test")));
+    assert_eq!(res.headers().get(),
+               Some(&reqwest::header::ContentLength(0)));
+}
+
+#[test]
+fn test_override_default_headers() {
+    use reqwest::header;
+    let mut headers = header::Headers::with_capacity(1);
+    headers.set(header::Authorization("iamatoken".to_string()));
+    let client = reqwest::Client::builder()
+        .default_headers(headers)
+        .build().unwrap();
+
+    let server = server! {
+        request: b"\
+            GET /3 HTTP/1.1\r\n\
+            Host: $HOST\r\n\
+            User-Agent: $USERAGENT\r\n\
+            Accept: */*\r\n\
+            Authorization: secret\r\n\
+            Accept-Encoding: gzip\r\n\
+            \r\n\
+            ",
+        response: b"\
+            HTTP/1.1 200 OK\r\n\
+            Server: test\r\n\
+            Content-Length: 0\r\n\
+            \r\n\
+            "
+    };
+
+    let url = format!("http://{}/3", server.addr());
+    let res = client.get(&url).header(header::Authorization("secret".to_string())).send().unwrap();
+
+    assert_eq!(res.url().as_str(), &url);
+    assert_eq!(res.status(), reqwest::StatusCode::Ok);
+    assert_eq!(res.headers().get(),
+               Some(&reqwest::header::Server::new("test")));
+    assert_eq!(res.headers().get(),
+               Some(&reqwest::header::ContentLength(0)));
+
+}
diff --git a/tests/gzip.rs b/tests/gzip.rs
index 15715c3..02a3083 100644
--- a/tests/gzip.rs
+++ b/tests/gzip.rs
@@ -114,8 +114,8 @@ fn test_accept_header_is_not_changed_if_set() {
         request: b"\
             GET /accept HTTP/1.1\r\n\
             Host: $HOST\r\n\
-            Accept: application/json\r\n\
             User-Agent: $USERAGENT\r\n\
+            Accept: application/json\r\n\
             Accept-Encoding: gzip\r\n\
             \r\n\
             ",
@@ -143,9 +143,9 @@ fn test_accept_encoding_header_is_not_changed_if_set() {
         request: b"\
             GET /accept-encoding HTTP/1.1\r\n\
             Host: $HOST\r\n\
-            Accept-Encoding: identity\r\n\
             User-Agent: $USERAGENT\r\n\
             Accept: */*\r\n\
+            Accept-Encoding: identity\r\n\
             \r\n\
             ",
         response: b"\
diff --git a/tests/multipart.rs b/tests/multipart.rs
index e832b33..723df31 100644
--- a/tests/multipart.rs
+++ b/tests/multipart.rs
@@ -19,10 +19,10 @@ fn test_multipart() {
         request: format!("\
             POST /multipart/1 HTTP/1.1\r\n\
             Host: $HOST\r\n\
-            Content-Type: multipart/form-data; boundary={}\r\n\
-            Content-Length: 123\r\n\
             User-Agent: $USERAGENT\r\n\
             Accept: */*\r\n\
+            Content-Type: multipart/form-data; boundary={}\r\n\
+            Content-Length: 123\r\n\
             Accept-Encoding: gzip\r\n\
             \r\n\
             {}\
diff --git a/tests/redirect.rs b/tests/redirect.rs
index ff46d5a..577f3e4 100644
--- a/tests/redirect.rs
+++ b/tests/redirect.rs
@@ -117,9 +117,9 @@ fn test_redirect_307_and_308_tries_to_post_again() {
             request: format!("\
                 POST /{} HTTP/1.1\r\n\
                 Host: $HOST\r\n\
-                Content-Length: 5\r\n\
                 User-Agent: $USERAGENT\r\n\
                 Accept: */*\r\n\
+                Content-Length: 5\r\n\
                 Accept-Encoding: gzip\r\n\
                 \r\n\
                 Hello\
@@ -136,9 +136,9 @@ fn test_redirect_307_and_308_tries_to_post_again() {
             request: format!("\
                 POST /dst HTTP/1.1\r\n\
                 Host: $HOST\r\n\
-                Content-Length: 5\r\n\
                 User-Agent: $USERAGENT\r\n\
                 Accept: */*\r\n\
+                Content-Length: 5\r\n\
                 Accept-Encoding: gzip\r\n\
                 Referer: http://$HOST/{}\r\n\
                 \r\n\
@@ -229,9 +229,9 @@ fn test_redirect_removes_sensitive_headers() {
         request: b"\
             GET /sensitive HTTP/1.1\r\n\
             Host: $HOST\r\n\
-            Cookie: foo=bar\r\n\
             User-Agent: $USERAGENT\r\n\
             Accept: */*\r\n\
+            Cookie: foo=bar\r\n\
             Accept-Encoding: gzip\r\n\
             \r\n\
             ",