diff --git a/src/aws/sdk/ec2.clj b/src/aws/sdk/ec2.clj
index b15911e..69c806f 100644
--- a/src/aws/sdk/ec2.clj
+++ b/src/aws/sdk/ec2.clj
@@ -23,6 +23,8 @@
            com.amazonaws.services.ec2.model.StopInstancesRequest
            com.amazonaws.services.ec2.model.Tag))
 
+(use 'clojure.string)
+
 (defn- ec2-client*
   "Create an AmazonEC2Client instance from a map of credentials."
   [cred]
diff --git a/test/aws/sdk/ec2_test.clj b/test/aws/sdk/ec2_test.clj
new file mode 100644
index 0000000..12c6371
--- /dev/null
+++ b/test/aws/sdk/ec2_test.clj
@@ -0,0 +1,53 @@
+(ns aws.sdk.ec2-test
+  (:use clojure.test
+        aws.sdk.ec2))
+
+
+;;
+;; filters
+;;
+
+(let [filter (aws-filter "foo" "bar")]
+
+  (deftest filter-is-a-vector
+    (testing "AWS filter provides a vector"
+      (is (vector? filter))))
+
+  (deftest filter-sets-name-and-one-value
+    (testing "AWS filter"
+    (let [f (first filter)]
+      (is (= (.getName f) "foo"))
+      (is (= (.getValues f) '("bar"))))))
+
+  (deftest filter-sets-two-values
+    (testing "AWS filter"
+      (let [filter (first (aws-filter "foo" "bar" "baz"))]
+        (is (= (.getValues filter) '("bar" "baz")))))))
+
+
+(let [filter (image-id-filter "foo")]
+
+  (deftest image-id-filter-is-a-describe-images-request
+    (testing "Image id filter is a DescribeImagesRequest"
+      (is (= (.getClass filter) com.amazonaws.services.ec2.model.DescribeImagesRequest))))
+
+  (let [f (first (.getFilters filter))]
+  
+    (deftest image-id-filter-sets-image-id-filter
+      (testing "Image id filter uses image-id filter"
+        (is (= (.getName f) "image-id"))))
+    
+    (deftest image-id-filter-sets-image-id
+      (testing "Image id filter uses given image id"
+        (is (= (first (.getValues f)) "foo"))))))
+
+
+(let [filter (image-owner-filter "foo")]
+
+  (deftest image-owner-filter-is-a-describe-images-request
+    (testing "Image owner filter is a DescribeImagesRequest"
+      (is (= (.getClass filter) com.amazonaws.services.ec2.model.DescribeImagesRequest))))
+
+  (deftest image-own-filter-sets-owner
+    (testing "Image owner filter sets a given owner"
+      (is (= (first (.getOwners filter)) "foo")))))