diff --git a/cast_test.go b/cast_test.go
index a202b7b..f9a24df 100644
--- a/cast_test.go
+++ b/cast_test.go
@@ -74,8 +74,43 @@ func TestErrorToString(t *testing.T) {
 func TestMaps(t *testing.T) {
 	var taxonomies = map[interface{}]interface{}{"tag": "tags", "group": "groups"}
 	var stringMapBool = map[interface{}]interface{}{"v1": true, "v2": false}
+
+	// ToStringMapString inputs/outputs
+	var stringMapString = map[string]string{"key 1": "value 1", "key 2": "value 2", "key 3": "value 3"}
+	var stringMapInterface = map[string]interface{}{"key 1": "value 1", "key 2": "value 2", "key 3": "value 3"}
+	var interfaceMapString = map[interface{}]string{"key 1": "value 1", "key 2": "value 2", "key 3": "value 3"}
+	var interfaceMapInterface = map[interface{}]interface{}{"key 1": "value 1", "key 2": "value 2", "key 3": "value 3"}
+
+	// ToStringMapStringSlice inputs/outputs
+	var stringMapStringSlice = map[string][]string{"key 1": []string{"value 1", "value 2", "value 3"}, "key 2": []string{"value 1", "value 2", "value 3"}, "key 3": []string{"value 1", "value 2", "value 3"}}
+	var stringMapInterfaceSlice = map[string][]interface{}{"key 1": []interface{}{"value 1", "value 2", "value 3"}, "key 2": []interface{}{"value 1", "value 2", "value 3"}, "key 3": []interface{}{"value 1", "value 2", "value 3"}}
+	var stringMapStringSingleSliceFieldsResult = map[string][]string{"key 1": []string{"value", "1"}, "key 2": []string{"value", "2"}, "key 3": []string{"value", "3"}}
+	var interfaceMapStringSlice = map[interface{}][]string{"key 1": []string{"value 1", "value 2", "value 3"}, "key 2": []string{"value 1", "value 2", "value 3"}, "key 3": []string{"value 1", "value 2", "value 3"}}
+	var interfaceMapInterfaceSlice = map[interface{}][]interface{}{"key 1": []interface{}{"value 1", "value 2", "value 3"}, "key 2": []interface{}{"value 1", "value 2", "value 3"}, "key 3": []interface{}{"value 1", "value 2", "value 3"}}
+
+	var stringMapStringSliceMultiple = map[string][]string{"key 1": []string{"value 1", "value 2", "value 3"}, "key 2": []string{"value 1", "value 2", "value 3"}, "key 3": []string{"value 1", "value 2", "value 3"}}
+	var stringMapStringSliceSingle = map[string][]string{"key 1": []string{"value 1"}, "key 2": []string{"value 2"}, "key 3": []string{"value 3"}}
+
 	assert.Equal(t, ToStringMap(taxonomies), map[string]interface{}{"tag": "tags", "group": "groups"})
 	assert.Equal(t, ToStringMapBool(stringMapBool), map[string]bool{"v1": true, "v2": false})
+
+	// ToStringMapString tests
+	assert.Equal(t, ToStringMapString(stringMapString), stringMapString)
+	assert.Equal(t, ToStringMapString(stringMapInterface), stringMapString)
+	assert.Equal(t, ToStringMapString(interfaceMapString), stringMapString)
+	assert.Equal(t, ToStringMapString(interfaceMapInterface), stringMapString)
+
+	// ToStringMapStringSlice tests
+	assert.Equal(t, ToStringMapStringSlice(stringMapStringSlice), stringMapStringSlice)
+	assert.Equal(t, ToStringMapStringSlice(stringMapInterfaceSlice), stringMapStringSlice)
+	assert.Equal(t, ToStringMapStringSlice(stringMapStringSliceMultiple), stringMapStringSlice)
+	assert.Equal(t, ToStringMapStringSlice(stringMapStringSliceMultiple), stringMapStringSlice)
+	assert.Equal(t, ToStringMapStringSlice(stringMapString), stringMapStringSliceSingle)
+	assert.Equal(t, ToStringMapStringSlice(stringMapInterface), stringMapStringSliceSingle)
+	assert.Equal(t, ToStringMapStringSlice(interfaceMapStringSlice), stringMapStringSlice)
+	assert.Equal(t, ToStringMapStringSlice(interfaceMapInterfaceSlice), stringMapStringSlice)
+	assert.Equal(t, ToStringMapStringSlice(interfaceMapString), stringMapStringSingleSliceFieldsResult)
+	assert.Equal(t, ToStringMapStringSlice(interfaceMapInterface), stringMapStringSingleSliceFieldsResult)
 }
 
 func TestSlices(t *testing.T) {
diff --git a/caste.go b/caste.go
index c9db07c..4972636 100644
--- a/caste.go
+++ b/caste.go
@@ -213,18 +213,23 @@ func ToStringMapStringE(i interface{}) (map[string]string, error) {
 	var m = map[string]string{}
 
 	switch v := i.(type) {
-	case map[interface{}]interface{}:
+	case map[string]string:
+		return v, nil
+	case map[string]interface{}:
 		for k, val := range v {
 			m[ToString(k)] = ToString(val)
 		}
 		return m, nil
-	case map[string]interface{}:
+	case map[interface{}]string:
+		for k, val := range v {
+			m[ToString(k)] = ToString(val)
+		}
+		return m, nil
+	case map[interface{}]interface{}:
 		for k, val := range v {
 			m[ToString(k)] = ToString(val)
 		}
 		return m, nil
-	case map[string]string:
-		return v, nil
 	default:
 		return m, fmt.Errorf("Unable to Cast %#v to map[string]string", i)
 	}
@@ -237,37 +242,51 @@ func ToStringMapStringSliceE(i interface{}) (map[string][]string, error) {
 	var m = map[string][]string{}
 
 	switch v := i.(type) {
-	case map[interface{}]interface{}:
+	case map[string][]string:
+		return v, nil
+	case map[string][]interface{}:
 		for k, val := range v {
 			m[ToString(k)] = ToStringSlice(val)
 		}
 		return m, nil
-	case map[interface{}][]interface{}:
+	case map[string]string:
+		for k, val := range v {
+			m[ToString(k)] = []string{val}
+		}
+	case map[string]interface{}:
+		for k, val := range v {
+			m[ToString(k)] = []string{ToString(val)}
+		}
+		return m, nil
+	case map[interface{}][]string:
 		for k, val := range v {
 			m[ToString(k)] = ToStringSlice(val)
 		}
 		return m, nil
-	case map[string][]interface{}:
+	case map[interface{}]string:
 		for k, val := range v {
 			m[ToString(k)] = ToStringSlice(val)
 		}
 		return m, nil
-	case map[string]interface{}:
+	case map[interface{}][]interface{}:
 		for k, val := range v {
-			m[ToString(k)] = []string{ToString(val)}
+			m[ToString(k)] = ToStringSlice(val)
 		}
 		return m, nil
-	case map[string][]string:
-		return v, nil
-	case map[string]string:
+	case map[interface{}]interface{}:
 		for k, val := range v {
-			m[ToString(k)] = []string{val}
+			key, err := ToStringE(k)
+			if err != nil {
+				return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
+			}
+			value, err := ToStringSliceE(val)
+			if err != nil {
+				return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
+			}
+			m[key] = value
 		}
-	default:
-		fmt.Printf("unexpected type %T", v)
-		return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
 	}
-	return m, fmt.Errorf("Unable to Cast %#v to map[string][]string", i)
+	return m, nil
 }
 
 func ToStringMapBoolE(i interface{}) (map[string]bool, error) {
@@ -353,7 +372,11 @@ func ToStringSliceE(i interface{}) ([]string, error) {
 	case string:
 		return strings.Fields(v), nil
 	default:
-		return a, fmt.Errorf("Unable to Cast %#v to []string", i)
+		str, err := ToStringE(v)
+		if err != nil {
+			return a, fmt.Errorf("Unable to Cast %#v to []string", i)
+		}
+		return []string{str}, nil
 	}
 
 	return a, fmt.Errorf("Unable to Cast %#v to []string", i)