diff --git a/lib/adapters/xhr.js b/lib/adapters/xhr.js
index f44bd45..2ad7e3e 100644
--- a/lib/adapters/xhr.js
+++ b/lib/adapters/xhr.js
@@ -27,7 +27,7 @@ module.exports = function xhrAdapter(resolve, reject, config) {
 
   // Create the request
   var request = new(XMLHttpRequest || ActiveXObject)('Microsoft.XMLHTTP');
-  request.open(config.method, buildUrl(config.url, config.params), true);
+  request.open(config.method.toUpperCase(), buildUrl(config.url, config.params), true);
 
   // Listen for ready state
   request.onreadystatechange = function () {
diff --git a/test/specs/interceptors.spec.js b/test/specs/interceptors.spec.js
index 8c7db25..5cb0427 100644
--- a/test/specs/interceptors.spec.js
+++ b/test/specs/interceptors.spec.js
@@ -63,7 +63,7 @@ describe('interceptors', function () {
         responseText: 'OK'
       });
 
-      expect(request.method).toBe('post');
+      expect(request.method).toBe('POST');
       expect(request.url).toBe('/bar');
     });
   });
diff --git a/test/specs/options.spec.js b/test/specs/options.spec.js
index 4a9fb1f..34969a4 100644
--- a/test/specs/options.spec.js
+++ b/test/specs/options.spec.js
@@ -21,7 +21,7 @@ describe('options', function () {
     }, 'waiting for the request', 100);
 
     runs(function () {
-      expect(request.method).toBe('get');
+      expect(request.method).toBe('GET');
     });
   });