diff --git a/common_service.h b/common_service.h
index 824ef97..dbf897e 100644
--- a/common_service.h
+++ b/common_service.h
@@ -20,6 +20,7 @@
 #include <inttypes.h>
 
 #include <string>
+#include <vector>
 
 #include <base/memory/ref_counted.h>
 #include <brillo/errors/error.h>
@@ -52,6 +53,13 @@
                      int32_t in_flags_as_int,
                      bool* out_result);
 
+  // Attempts a DLC install operation.
+  // |omaha_url|: the URL to query for update.
+  // |dlc_ids|: a list of DLC IDs.
+  bool AttemptInstall(brillo::ErrorPtr* error,
+                      const std::string& omaha_url,
+                      const std::vector<std::string>& dlc_ids);
+
   bool AttemptRollback(brillo::ErrorPtr* error, bool in_powerwash);
 
   // Checks if the system rollback is available by verifying if the secondary