diff --git a/CHANGELOG.md b/CHANGELOG.md
index bb9d9535..e57a61ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,9 @@
 
 * Fix a few more small `@extend` bugs.
 
+* Fix a bug where interpolation in a quoted string was being dropped in some
+  circumstances.
+
 ## 1.0.0-alpha.6
 
 * Allow `var()` to be passed to `rgb()`, `rgba()`, `hsl()`, and `hsla()`.
diff --git a/lib/src/ast/sass/expression/string.dart b/lib/src/ast/sass/expression/string.dart
index 679eb0b8..3d7ec32a 100644
--- a/lib/src/ast/sass/expression/string.dart
+++ b/lib/src/ast/sass/expression/string.dart
@@ -55,8 +55,9 @@ class StringExpression implements Expression {
     var buffer = new InterpolationBuffer();
     if (quote != null) buffer.writeCharCode(quote);
     for (var value in text.contents) {
-      if (value is Interpolation) {
-        buffer.addInterpolation(value);
+      assert(value is Expression || value is String);
+      if (value is Expression) {
+        buffer.add(value);
       } else if (value is String) {
         for (var i = 0; i < value.length; i++) {
           var codeUnit = value.codeUnitAt(i);